<PAGE>
 
                                                                      Exhibit 3a
                              BOOK 422 PAGE 0720
                                                                          PAGE 1

                               State of Delaware

19411
                              LOGO/OFFICIAL SEAL


                         Office of Secretary of State
                             --------------------

     I, MICHAEL HARKINS, SECRETARY OF STATE OF THE STATE OF DELAWARE DO HEREBY
CERTIFY THE ATTACHED IS A TRUE AND CORRECT COPY OF THE CERTIFICATE OF
INCORPORATION OF CITIZENS FINANCIAL CORP.  FILED IN THIS OFFICE ON THE SECOND
DAY OF OCTOBER, A.D. 1986, AT 9 O'CLOCK A.M.

                              | | | | | | | | | |









DEPARTMENT OF STATE
OF DELAWARE

LOGO/OFFICIAL SEAL                        /s/ Michael Harkins
                                        ----------------------------------------
                                          Michael Harkins, Secretary of State
OFFICE OF THE                       AUTHENTICATION:    |0962723
SECRETARY OF STATE                  DATE:  10/02/1986

862750160
<PAGE>
 
                                                              Exhibit 3a (cont.)

                              BOOK 422 PAGE 0721
                                                            FILED
                                                            OCT 2, 1986

                         CERTIFICATE OF INCORPORATION

                                      OF

                           CITIZENS FINANCIAL CORP.

     The undersigned incorporators do hereby incorporate or organize a
corporation under the General Corporation Law of Delaware, for the purpose and
on the terms hereinafter set forth:

     FIRST.  The name of this corporation shall be CITIZENS FINANCIAL CORP.

     SECOND.  The corporation's registered office in the State of Delaware shall
be at 4305 Lancaster Pike, in the City of Wilmington, New Castle County,
Delaware.  The corporation's registered agent at such address shall be
Corporation Service Company, whose mailing address is P.O. Box 591, Wilmington,
Delaware 19899.

     THIRD.  The purposes of this corporation are, primarily, to purchase, own
and hold the stock of national banking associations, state banking institutions
and other corporations, subject to such regulatory approval as may be required,
to perform such actions as may be usual and customary in directing the
operations of the entities so acquired, and, generally, to engage in any lawful
act or activity for  which corporations may be organized under the General
Corporation Law of Delaware.

     FOURTH.  The corporation shall have authority to issue 250,000 shares of
stock, and the par value of each such share shall be Ten Dollars ($10.00).

     FIFTH.  The names and mailing addresses of the incorporators are as
follows:

     Max L. Armentrout    Route 1, Box 306A
                          Chenoweth Creek Road
                          Elkins, WV  26241

     Raymond L. Fair      Route 1
                          Chenoweth Creek Road
                          Elkins, WV  26241
<PAGE>
 
                                                              Exhibit 3a (cont.)

                              BOOK 422 PAGE 0722


     John F. Harris       1008 South Davis Avenue
                          Elkins, WV  26241

     Emery Thompson, Jr.  317 Wilson Street
                          Elkins, WV  26241

     L. T. Williams       Route 2, Box 6
                          Elkins, WV  26241

     SIXTH.  The powers of the incorporators shall terminate upon the filling of
this Certificate of Incorporation, and the names and mailing addresses of the
persons who are to serve as directors until the first annual meeting of
stockholders or until their successors are elected and qualified are as follows:

     Max L. Armentrout    Route 1, Box 306A
                          Chenoweth Creek Road
                          Elkins, WV  26241

     Raymond L. Fair      Route 1
                          Chenoweth Creek Road
                          Elkins, WV  26241
 
     John F. Harris       1008 South Davis Avenue
                          Elkins, WV  26241
 
     W. H. Scheel, Jr.    Box 2207
                          Elkins, WV  26241

     Emery Thompson, Jr.  317 Wilson Street
                          Elkins, WV  26241

     L. T. Williams       Route 2, Box 6
                          Elkins, WV  26241

     SEVENTH.  The following provisions shall apply to the management of the
business and to the conduct of the affairs of the corporation:

     (A)  Directors.  The board of directors shall consist of not less than five
          ---------                                                             
(5) nor more than twenty-five (25) stockholders, the exact number to be fixed
and determined from time to time by resolution of a majority of the stockholders
at any annual or special meeting thereof.  The directors shall be divided into
three classes, as nearly equal in number as possible, to be designated as Class
1, consisting of not more than eight (8) directors; Class 2, consisting of not
more than eight (8) directors; and Class 3, consisting of not more than nine (9)
directors.
<PAGE>
 
                                                              Exhibit 3a (cont.)
                              BOOK 422 PAGE 0723

The term of office of the initial directors of Class 1 shall expire at the first
annual meeting of stockholders following their election, and their successors
shall be elected for three-year terms.  The term of office of the initial
directors of Class 2 shall expire at the second annual meeting of stockholders
following their election, and their successors shall be elected to three-year
terms.  The term of office of the initial directors of Class 3 shall expire at
the third annual meeting of stockholders following their election, and their
successors shall be elected to three-year terms.  Thereafter, all directors
shall be elected to three-year terms.  Each director shall serve until his or
her successor shall have been elected and shall qualify or until his or her
earlier resignation or removal.

     (B)  Cumulative Voting.  Each stockholder shall be entitled to one vote for
          -----------------                                                     
each share of stock held by such stockholder.  No stockholder shall have the
right to cumulate his or her votes with respect to any election of directors.

     (C)  Tender Offers.  The board of directors, if it deems it advisable, may
          -------------                                                        
oppose a tender of other offer for the corporation's securities, whether the
offer is in cash or securities of a corporation or otherwise.  When considering
whether to oppose an offer, the board of directors shall consider all pertinent
issues which, by way of illustration and not of limitation, may include any and
all of the following:

     (1)  Whether the offer price is acceptable based on the historical and
present operating results or financial condition of the corporation;

     (2)  Whether a more favorable price could be obtained for the corporation's
securities in the future;

     (3)  The impact which an acquisition of the corporation would have on the
employees, depositors, or customers of the corporation and its subsidiaries in
the community which they serve;
<PAGE>
 
                                                              Exhibit 3a (cont.)
                              BOOK 422 PAGE 0724

     (4)  The reputation and business practices of the offeror and its
management and affiliates as they would affect the employees, depositors and
customers of the corporation and its subsidiaries and the future value of the
corporation's stock;

     (5)  The value of the securities, if any, which the offeror is offering in
exchange for the corporation's securities, based on analysis of the worth of the
corporation as compared to the corporation or other entity whose securities are
being offered;

     (6)  Any antitrust or other legal or regulatory issues that are raised by
the offeror.

     If the board of directors upon consideration of all pertinent issues
determines that an offer should be rejected or opposed, it may take nay lawful
action to accomplish such purpose, including, but not limited to any and all of
the following:  Advising stockholders not to accept the offer; litigation
against the offeror; filing complaints with all governmental and regulatory
authorities; issuing the authorized but unissued securities or treasury stock of
the corporation or granting options with respect thereto; and obtaining a more
favorable offer from an individual or other entity.

     (D)  Preemptive Rights.  No stockholder shall have any preemptive right to
          -----------------                                                    
subscribe to any additional issue of stock of the corporation or to any security
convertible into such stock.

     (E)  Directors' Personal Liability.  No director shall be personally liable
          -----------------------------                                         
to the corporation or its stockholders for monetary damages for any breach of
fiduciary duty by such director as a director.  Notwithstanding the foregoing
sentence, a director shall be liable to the extent provided by applicable law
(i) for breach of the director's duty of loyalty to the corporation or its
stockholders, (ii) for acts or omissions not in good faith or which involve
intentional misconduct or a knowing violation of law, (iii) pursuant to Section
174 of the Delaware
<PAGE>
 
                                                              Exhibit 3a (cont.)
                              BOOK 422 PAGE 0725

General Corporation Law or (iv) for any transaction from which the director
derived an improper personal benefit.  No amendment to or repeal of the Article
SEVENTH (E) shall apply to or have any effect on the liability or alleged
liability of any director of the corporation for or with respect to any acts or
omissions of such director occurring prior to such amendment.

     (F)  Directors' and Officers' Liability Insurance.  The corporation shall
          --------------------------------------------                        
use its best efforts to purchase and maintain insurance, on behalf of any person
who is or was director of officer of the corporation, or is or was serving at
the request of the corporation as a director or officer of another corporation
or other enterprise, in such amount or limits as may from time to time be
determined to be reasonable as provided in the by-laws, against any liability
asserted against such person and incurred by him or her in any such capacity, or
arising out of his or her status as such director or officer, whether or not the
corporation would have the power to indemnify him or her against such liability
under law.  This provision for directors' and officers' liability insurance is
in addition to and not exclusive of all other rights to which directors or
officers seeking indemnification may be entitled under any law, by-law,
agreement, vote of stockholders or disinterested directors, or otherwise.

     (G)  By-laws.  All other provisions, not inconsistent with law or with this
          -------                                                               
Certificate of Incorporation, relating to the business of the corporation, the
conduct of its affairs and its rights or powers or the rights or powers of its
stockholders, director or officers, shall be established by the by-laws.  The
power to adopt, amend or repeal by-laws is hereby conferred upon the directors,
to the extent permitted by law.

     THE UNDERSIGNED INCORPORATORS, for the purpose of forming a corporation
under the laws of the State of Delaware, do make, file and record this
Certificate of Incorporation and do certify that the facts
<PAGE>
 
                                                              Exhibit 3a (cont.)
                              BOOK 422 PAGE 0726

herein are true; and we have accordingly set our respective hands to duplicate
originals hereof this  29th  day of  September , 1986.
                      ------        -----------       
                                                 /s/ Max L. Armentrout
                                               ---------------------------------
                                               MAX L. ARMENTROUT, INCORPORATOR


                                                 /s/ Raymond L. Fair
                                               ---------------------------------
                                               RAYMOND L. FAIR, INCORPORATOR


                                                 /s/ John F. Harris
                                               ---------------------------------
                                               JOHN F. HARRIS, INCORPORATOR


                                                 /s/ Emery Thompson, Jr.
                                               ---------------------------------
                                               EMERY THOMPSON, JR., INCORPORATOR


                                                 /s/ L. T. Williams
                                               ---------------------------------
                                               L. T. WILLIAMS, INCORPORATOR


STATE OF WEST VIRGINIA,

COUNTY OF RANDOLPH, to-wit:

     The undersigned notary public in and for the county and state aforesaid
does hereby certify that MAX L. ARMENTROUT, RAYMOND L. FAIR, JOHN F. HARRIS,
EMERY THOMPSON, JR. AND L. T. WILLIAMS, whose names are signed to the forgoing
Certificate of Incorporation bearing date the 29th day of September , 1986, this
                                             ------      -----------
day personally appeared before me in my said county and severally acknowledged
that such instrument is the act and deed of each and all of them and that the
facts stated therein are true.

     GIVEN under my hand and official seal this  29th  day of  September , 1986.
                                                ------        -----------       


                                                /s/ Frank A. Jackson
Official Seal:                                ----------------------------------
                                              Frank A. Jackson, Notary Public
 STAMP

This instrument prepared by:
 Richard G. Herndon                           RECEIVED FOR RECORD
 F. A. Jackson                                    OCT 6, 1986
 Attorneys-at-Law                             LEO J. DUGAN, JR., Recorder
 84 Fifteenth Street
 Wheeling, WV  26003
<PAGE>
 
                                                              Exhibit 3a (cont.)

                                                                          PAGE 1
                               State of Delaware

                       Office of the Secretary of State

                       --------------------------------


     I, WILLIAM T. QUILLEN, SECRETARY OF STATE OF THE STATE OF DELAWARE, DO
HEREBY CERTIFY THE ATTACHED IS A TRUE AND CORRECT COPY OF THE CERTIFICATE OF
AMENDMENT OF "CITIZENS FINANCIAL CORP." FILED IN THIS OFFICE ON THE TWENTIETH
DAY OF APRIL, A.D. 1993, AT 9 O'CLOCK A.M.

     A CERTIFIED COPY OF THIS CERTIFICATE HAS BEEN FORWARDED TO NEW CASTLE
COUNTY RECORDER OF DEEDS FOR RECORDING.

                              * * * * * * * * * *



                                            /s/ William T. Quillen
                                          --------------------------------------
                                          William T. Quillen, Secretary of State

                                          AUTHENTICATION: *3868804
                                          DATE:  04/22/1993


713110004
<PAGE>
 
                                                              Exhibit 3a (cont.)

                                                                          Page 1
                           CERTIFICATE OF AMENDMENT
                                      TO
                         CERTIFICATE OF INCORPORATION
                                      OF
                           CITIZENS FINANCIAL CORP.


CITIZENS FINANCIAL CORP., a corporation organized and existing under and by
virtue of the

General Corporation Law of the State of Delaware, DOES HEREBY CERTIFY as
follows:

     FIRST:  That the Board of Directors of said corporation, at a meeting duly
convened and held on the 17th day of March, 1993 adopted the following
resolution:

           BE IT RESOLVED by the Board of Directors of Citizens Financial Corp.:

           Section 1.  The Board of Directors does hereby declare the
     advisability of amending Article FOURTH of the corporation's Certificate of
     Incorporation, heretofore filed in the office of the Secretary of State of
     the State of Delaware on October 2, 1986, to increase the authorized
     capital stock of the corporation from two hundred fifty thousand (250,000)
     shares to one million two hundred fifty thousand (1,250,000) shares and to
     reduce the par value of each such share from ten dollars ($10.00) per share
     to two dollars ($2.00) per share, the said Article FOURTH to read in its
     entirety as follows:

                    FOURTH.  The corporation shall have authority to issue one
          million two hundred fifty thousand (1,250,000) shares of stock, and
          the par value of each such share shall be two dollars ($2.00).

     The corporation's capital shall remain unchanged by this amendment.

           Section 2.  The Board of Directors hereby directs that the
     aforesaid amendment as proposed shall be considered at the next annual
     meeting of stockholders, to be convened on April 17, 1993.  Such annual
     meeting shall be called and held upon such notice as is provided by law,
     and the notice shall set forth such amendment in full.

           Section 3.  If at such meeting a majority of the outstanding
     stock entitled to vote thereon is voted in favor of such amendment, a
     certificate setting forth the amendment shall be executed and acknowledged
     by the chairman or vice-chairman of the Board of Directors or by the
     president or a vice-president and shall be filed with the Secretary of
     State for the State of Delaware.  The secretary or an assistant secretary
     shall attest the signature of the chairman, vice-chairman, president or
     vice-president.  Such certificate shall certify that such amendment has
     been duly adopted in accordance with law, and a certified copy thereof
     shall be recorded and indexed int he office of the county recorder for New
     Castle County, Delaware.

           Section 4.  The Board of Directors does hereby declare that upon
     filing of the aforesaid certificate of amendment, every stockholder of
     record as of March 16, 1993 shall be entitled to receive a certificate
     representing four (4) additional shares of the corporation's capital stock
     for each share of capital stock heretofore issued and outstanding and held
     by such stockholder. Certificates heretofore issued and representing
     capital stock of the corporation shall not be required to be surrendered or
     exchanged but shall continue to represent the same number of shares of the
     corporation's capital stock, and the par value of all such shares
     theretofore issued and outstanding shall be deemed to be two dollars
     ($2.00) per share, regardless of any par value which may be stated on the
     certificates representing such shares.

           Section 5.  The officers are hereby authorized to perform all
     acts which in their opinion may be necessary or useful in effecting the
     actions contemplated by this resolution; to employ counsel, certified
     public accountants, consultants and others as deemed necessary; to execute
     all filings, amendments and other documents as may be necessary; and to
     give such further assurances as may be required.  The officers shall give
     prompt notice of this resolution to the stockholders of the corporation.
<PAGE>
 
                                                              Exhibit 3a (cont.)

                                                                          Page 2

     SECOND:  That the proposed amendment was considered at the annual meeting
of the stockholders, convened on April 17, 1993, called and held upon such
notice as is provided by law, which notice set forth such amendment in full, and
that a majority of the outstanding stock entitled to vote thereon voted in favor
of the amendment, in accordance with the provisions of Section 242 of the
General Corporation Law of the State of Delaware.

     IN WITNESS WHEREOF, the said corporation has caused this Certificate to be
signed on its behalf by its President, and attested by its Secretary, this 17th
day of April, 1993.


                                    CITIZENS FINANCIAL CORP.


                                  By  /s/ Emery Thompson, Jr.
                                     --------------------------------------
                                          Its President


                         Attested By  /s/ Robert J. Schoonover
                                     --------------------------------------
                                          Its Secretary