<PAGE>   1
                                                                     EXHIBIT 3.1

                                    RESTATED
                          CERTIFICATE OF INCORPORATION
                                       OF
                           GLOBAL VACATION GROUP, INC.
                            UNDER SECTION 807 OF THE
                            BUSINESS CORPORATION LAW


          The undersigned, being, respectively the President and the Secretary
of Global Vacation Group, Inc. (the "CORPORATION"), do hereby certify as
follows:

          1. The name of the Corporation is Global Vacation Group, Inc. The name
under which the corporation originally was formed is Allied Bus Corp.

          2. The Certificate of Incorporation originally was filed with the
Department of State of New York on July 17, 1959.

          3. The Restated Certificate of Incorporation of the Corporation as now
in full force and effect hereby is amended to effect the following changes as
authorized by Section 801 of the New York Business Corporation Law (the
"NYBCL"):

     (a)  To remove from the authorized capital stock of the Corporation the
class of stock designated as Class A Convertible Preferred Stock, $1,000 par
value per share (the "CLASS A PREFERRED");

     (b)  To delete Section 5.1(c) from the Corporation's Restated
Certificate of Incorporation, which Section 5.1(c) related to the combination of
shares of the Corporation's common stock, $.01 par value per share, which was
consummated prior to the date of this Restated Certificate of Incorporation;

     (c)  To delete Article VI from the Corporation's Restated Certificate of
Incorporation, which Article VI related to the rights and privileges of the
Class A Preferred, and to delete all other references to the Class A Preferred
from the Corporation's Restated Certificate of Incorporation;

     (d)  To delete references to the Corporation's initial public offering and
other events related to such offering, all of which were consummated prior to
the date of this Restated Certificate of Incorporation;

     (e)  To amend Section 7.3 of the Corporation's Restated Certificate
of Incorporation to identify the directors of the Corporation and the classes
into which such directors shall be divided;

     (f)  To delete Section 9.2 from the Corporation's Restated
Certificate of Incorporation, which Section 9.2 related to the right


                                       28
<PAGE>   2
of the Corporation's shareholders to take action by written consent prior to the
completion of the Corporation's initial public offering; and

     (g)  To make certain clarifying amendments to Section 12.1 and
Section 12.3.

          4. To effect the foregoing amendments, the Restated Certificate of
Incorporation of the Corporation hereby is amended and restated in its entirety
to read as follows:



                                   ARTICLE I

          The name of the Corporation is Global Vacation Group, Inc.



                                   ARTICLE II

          The office of the Corporation in the State of New York is located in
the County of New York.



                                   ARTICLE III

          The Secretary of State is designated as agent of the Corporation upon
whom process against it may be served. The address to which the Secretary of
State shall mail a copy of any process against the Corporation served upon him
or her is 1420 New York Avenue, N.W., Suite 550, Washington, D.C. 20005.

          The name and address of the registered agent of the corporation upon
whom process against the corporation may be served is CT Corporation System,
1633 Broadway, New York, NY 10019.



                                   ARTICLE IV

          The nature of the business of the Corporation and the purposes for
which it is organized are to engage in any lawful act or activity for which
corporations may be organized under the NYBCL; provided, that the Corporation is
not formed to engage in any act or activity requiring the consent or approval of
any state official, department, board, agency or other body without such consent
or approval first being obtained.



                                   ARTICLE V

      5.1. CAPITAL STOCK.

          (a) CLASSES. The total number of shares of all classes of stock which
the Corporation shall have authority to issue is 

                                       29
<PAGE>   3

66,000,000, of which (a) 60,000,000 shares shall be common stock, $.01 par value
per share ("COMMON STOCK"), and (b) 6,000,000 shares shall be preferred stock,
$.01 par value per share ("PREFERRED STOCK").

          (b) NO PREEMPTIVE RIGHTS. No shareholder of the Corporation shall have
any preemptive rights to purchase, subscribe for or otherwise acquire any
capital stock or other securities of the Corporation, whether now or hereafter
authorized, and any and all preemptive rights hereby are denied.

      5.2. COMMON STOCK. The powers, designations, preferences and relative
participating, optional or other special rights and the qualifications,
limitations and restrictions of the Common Stock are as follows:

          (a) DIVIDENDS. Subject to the rights of the holders of Preferred
Stock, the holders of the Common Stock shall be entitled to receive when, as,
and if declared by the Board of Directors of the Corporation (the "BOARD"), out
of funds legally available therefor, dividends payable in cash, stock or
otherwise.

          (b) DISTRIBUTIONS UPON LIQUIDATION. In the event of a voluntary or
involuntary liquidation, dissolution or winding up of the Corporation, and after
the holders of Preferred Stock shall have received the full preferential amounts
(if any) to which such holders are entitled, the holders of Common Stock shall
be entitled to share in the distribution of any remaining assets available for
distribution to the holders of Common Stock.

          (c) VOTING RIGHTS. Subject to the voting rights granted to the holders
of Preferred Stock, the holders of Common Stock shall be entitled to one (1)
vote per share in voting on the election of directors and for all other
corporate purposes.

      5.3. PREFERRED STOCK. The Corporation shall have the authority to issue 
shares of Preferred Stock. The Board hereby is authorized, without further
shareholder approval, to issue shares of Preferred Stock in one or more series
and to fix the rights, preferences, privileges and restrictions thereof,
including dividend rights, voting rights, terms of redemption and liquidation
preferences, and to fix the number of shares constituting any series and the
designations of such series.



                                   ARTICLE VI

                                   [RESERVED]



                                   ARTICLE VII

      7.1. POWER OF BOARD AND QUALIFICATION OF DIRECTORS. The business of the
Corporation shall be managed by the Board. Each director shall be at least
18 years of age.

                                       30
<PAGE>   4

      7.2. NUMBER OF DIRECTORS. The number of directors of the Corporation  
shall  be not less than three (3) nor more than fifteen (15), and shall be fixed
from time to time by the affirmative vote of more than two-thirds (2/3) of the
total number of directors which the Corporation would have, prior to any
increase or decrease, if there were no vacancies.

      7.3. CLASSES, ELECTION AND TERM. The Board shall be divided into three (3)
classes, with each class to be as nearly equal in number as reasonably possible.
The term of office of each class of directors shall be three years and shall
expire in successive years at the time of the annual meeting of shareholders.
Effective as of the date this Restated Certificate of Incorporation is filed
with the Department of State of the State of New York, the identity of the
directors of the Corporation and the classes into which such directors shall be
divided shall be as follows:

      Class I (term of office expiring at the 1999 annual meeting of
shareholders) -- Kenneth M. Duberstein;

      Class II (term of office expiring at the 2000 annual meeting of
shareholders) -- Carl J. Rickertsen and James M. Sullivan; and

      Class III (term of office expiring at the 2001 annual meeting of
shareholders) -- Roger H. Ballou and Frederic V. Malek.

      Directors elected to succeed those directors whose terms have expired at
an annual meeting shall be elected for a term of office to expire at the third
succeeding annual meeting of shareholders after their election, and upon the
election and qualification of their successors. If the number of directors is
changed, any increase or decrease shall be apportioned among the classes so as
to maintain or attain the number of directors in each class as nearly equal as
reasonably possible, but in no case shall a decrease in the number of directors
shorten the term of any incumbent director.

      7.4. RESIGNATIONS. Any director of the Corporation may resign at any time
by giving written notice to the Board or to the Chairman of the Board or to the
Secretary of the Corporation. Such resignation shall take effect at the time
specified therein, and unless otherwise specified therein the acceptance of such
resignation shall not be necessary to make it effective.

      7.5. REMOVAL OF DIRECTORS. Except as may be provided in a resolution which
provides for any class of Preferred Stock pursuant to Article V hereof and which
relates to such class of Preferred Stock, (i) any one or more directors may be
removed only for cause by the affirmative vote of a majority of the directors
then in office and (ii) any or all of the directors may be removed only for
cause by the affirmative vote of the holders of at least sixty-six and
two-thirds percent (66 2/3%) of the combined voting power of all of the shares
of all classes of capital stock of the Corporation then entitled to vote
generally in the election of directors.

  
                                     31


<PAGE>   5

      7.6. NEWLY CREATED DIRECTORSHIPS AND VACANCIES. Except as may be provided
in a resolution which provides for any class of Preferred Stock pursuant to
Article V hereof and which relates to such class of Preferred Stock, newly
created directorships resulting from an increase in the number of directors and
vacancies occurring in the Board for any reason may be filled only by vote of a
majority of the directors then in office, even if less than a quorum exists. A
director elected by the Board to fill a vacancy shall be elected to hold office
until the next annual meeting of shareholders and until such director's
successor has been elected and qualified.



                                  ARTICLE VIII

          The Board shall have the power to adopt, amend, alter, change or 
repeal the By-laws. In addition to any requirements of the NYBCL (and
notwithstanding the fact that a lesser percentage may be specified by the
NYBCL), any adoption, amendment, alteration, change or repeal of any By-laws by
the shareholders of the Corporation shall require the affirmative vote of the
holders of at least sixty-six and two-thirds percent (66 2/3%) of the combined
voting power of all of the shares of all classes of capital stock of the
Corporation then entitled to vote generally in the election of directors.



                                   ARTICLE IX

      9.1. SPECIAL MEETING OF SHAREHOLDERS. Special meetings of shareholders may
only be called by the Board, the Chairman of the Board or the Chief Executive
Officer. At such meetings, the only business which may be transacted is that
relating to the purpose or purposes set forth in the notice thereof.

      9.2. [RESERVED]

      9.3. NO ACTION BY WRITTEN CONSENT OF SHAREHOLDERS. Except as may be
provided in a resolution of the Board which provides for any class or series of
Preferred Stock pursuant to Article V hereof and which relates to such class of
Preferred Stock, any action required or permitted to be taken by the
shareholders of the Corporation must be effected at a duly called annual or
special meeting of such shareholders as provided in the By-laws and may not be
effected by any consent in writing by any such shareholders.



                                    ARTICLE X

          A director of the Corporation shall, to the maximum extent permitted
by the NYBCL, have no personal liability to the Corporation or its shareholders
for monetary damages for breach of fiduciary duty as a director. If the NYBCL
hereafter is amended to eliminate or further limit the liability of a director,
then a director of the Corporation, in addition to the circumstances in which a
director is 

                                       32

<PAGE>   6

not personally liable as set forth in the preceding sentence, shall have no such
liability to the fullest extent permitted by the amended NYBCL. Any repeal or
modification of this Article X by the shareholders of the Corporation shall not
adversely affect any right or protection of a director of the Corporation
existing at the time of such repeal or modification.



                                   ARTICLE XI

          The Corporation shall have authority, to the fullest extent now or
hereafter permitted by the NYBCL, or by any other applicable law, and to the
extent and in the manner provided in the By-laws, to enter into any contract or
transaction with one or more of its directors or officers, or with any
corporation, partnership, joint venture, trust, association, or other entity in
which one or more of its directors or officers are directors or officers, or
have a financial interest, notwithstanding such relationships and
notwithstanding the fact that the director or officer is present at or
participates in the meeting of the Board or committee thereof which authorizes
the contract or transaction.



                                   ARTICLE XII

      12.1. GENERAL RIGHT TO AMEND RESTATED CERTIFICATE OF INCORPORATION. The
Corporation hereby reserves the right to amend, alter, change or repeal any
provision contained in this Restated Certificate of Incorporation, and all
rights conferred upon shareholders are granted subject to this reservation.
Except as may be provided in a resolution which provides for any class of
Preferred Stock pursuant to Article V hereof and which relates to such class of
Preferred Stock, any such amendment, alteration, change or repeal shall require
the affirmative vote of both (a) a majority of the members of the Board then in
office and (b) except as provided in Section 12.3 below, a majority of the
combined voting power of all of the shares of all classes of capital stock of
the Corporation then entitled to vote generally in the election of directors.

      12.2. ABANDONMENT OF PROPOSED AMENDMENT. By a vote of the majority of the
members of the Board then in office, the Board may adopt a resolution providing
that at any time prior to the filing of any such amendment with the Secretary of
State, notwithstanding authorization of the proposed amendment by the
shareholders, the Board may abandon such proposed amendment without further
action by the shareholders.

      12.3. AMENDMENT OF CERTAIN PROVISIONS. Notwithstanding anything contained
in this Restated Certificate of Incorporation to the contrary, the affirmative
vote of both (a) a majority of the members of the Board then in office and (b)
except as may be provided in a resolution which provides for any class of
Preferred Stock pursuant to Article V hereof and which relates to such class of
Preferred Stock, the holders of at least sixty-six and two-thirds 

                                      33

<PAGE>   7

percent (66 2/3%) of the combined voting power of all of the shares of all
classes of capital stock of the Corporation then entitled to vote generally in
the election of directors shall be required to amend, repeal or adopt any
provision inconsistent with Section 7.3, Section 7.5, Section 7.6, Article VIII
or Article IX hereof or this Section 12.3.



                                  ARTICLE XIII

          The duration of the Corporation is to be perpetual.



                                   * * * *

          5. This Restated Certificate of Incorporation has been approved by the
unanimous written consent of the Board and by the written consent of the holders
of the requisite number of the outstanding shares of the Corporation's capital
stock.





      IN WITNESS WHEREOF, the undersigned have executed this Restated
Certificate of Incorporation as of this 6th day of August, 1998 and we affirm
the statements contained herein are true under the penalties of perjury.




                                       /s/ Daniel A. Raskas
                                       ----------------------------------------
                                       Daniel A. Raskas, Vice President and
                                       Secretary




                                       /s/ Christopher Temple
                                       ----------------------------------------
                                       Christopher Temple, Assistant Secretary




                                       34