March 10, 1999



      Mr. J. Shelby Bryan


      Dear Mr. Bryan:

                  Reference  is made to the Stock  Option  Agreement  between J.
      Shelby Bryan and IntelCom  Group Inc. (now known as ICG Holdings  (Canada)
      Co.  (the  "Company"),  dated as of November  13, 1995 (the  "Agreement"),
      which grants Mr. Bryan an option to purchase an aggregate  200,000  Common
      Shares,  no par value,  of the Company at $10.00 per share.  The Agreement
      was assumed by ICG  Communications,  Inc., a Delaware  corporation and the
      parent  corporation  of the Company  ("ICG"),  pursuant to the terms of an
      Agreement and Support  Agreement,  dated as of June 27, 1996,  between the
      Company and ICG. In addition,  the  Agreement  was  previously  amended by
      letter   agreement   dated   September  10,  1996,   whereby   Section  5.
      Non-transferability of Option was deleted in its entirety, and was further
      amended by letter agreement dated October 27, 1998, pursuant to which "S&P
      500 Index"  references in the Agreement were replaced by references to the
      "Russell 2000 Index."

                  The Company,  ICG and Mr. Bryan hereby  further amend Sections
      6, 7 and 9 of the  Agreement  to provide  that the Option (as such term is
      defined in the  Agreement)  shall expire on the tenth  anniversary  of the
      original  date  of  grant  and  shall  neither  be  forfeited  due  to the
      Employee's voluntary termination of employment,  retirement, disability or
      death nor be subject to earlier  termination  thereof.  In order to effect
      such amendments,

                a) Section 6(a) shall read in its entirety as follows:

               (a) If the  Employee  at any time ceases to be an employee of the
          Company and of any Parent or Subsidiary by reason of his discharge for
          Good Cause (as defined below),  the Option shall  forthwith  terminate
          and the Employee shall forfeit all rights hereunder.  If, however, the
          Employee  for any  other  reason  ceases to be such an  employee,  the
          Option  may,  subject  to the  provisions  of  Section  8  hereof,  be
          exercised by the  Employee to the same extent the Employee  would have
          been entitled under Section 3 hereof to exercise the Option on the day
          next preceding the date of such  cessation of employment,  at any time
          within the period  ending ten (10) years  after the Date of Grant,  at
          the end of which period the Option,  to the extent not then exercised,
          shall

<PAGE>
                                       2


          terminate and the Employee shall forfeit all rights hereunder, even if
          the Employee  subsequently returns to the employ of the Company or any
          Parent  or  Subsidiary.  In no  event,  however,  may  the  Option  be
          exercised  after the  expiration  of the term  provided  in  Section 4
          hereof.  For purposes of this  Agreement,  "Good Cause" shall mean (i)
          the  Employee's  willful  or  gross  misconduct  or  willful  or gross
          negligence in the performance of his duties for the Company or for any
          parent or  subsidiary  corporation  of the Company after prior written
          notice of such  misconduct or negligence and the  continuance  thereof
          for a period of 30 days after  receipt by the Employee of such notice,
          (ii) the Employee's  intentional or habitual neglect of his duties for
          the Company or for any parent or subsidiary corporation of the Company
          after prior written  notice of such neglect,  or (iii) the  Employee's
          theft or  misappropriation of funds of the Company or of any parent or
          subsidiary corporation of the Company or commission of a felony.

                  b) Section 7 shall read in its entirety as follows:


               7.Exercise  Upon Death or  Disability.  (a) If the Employee  dies
          while he is  employed  by the  Company or by any parent or  subsidiary
          corporation  of the  Company  (or within  three (3)  months  after his
          retirement  from the  Company),  and on or after the  first  date upon
          which he would have been  entitled  to exercise  the Option  under the
          provisions  of  Section 3  hereof,  the  Option  may,  subject  to the
          provisions  of Sections 5 and 8 hereof,  be exercised  with respect to
          all or any part of the shares of Common Stock as to which the deceased
          Employee  had not  exercised  the Option at the time of his death (but
          only to the extent the Option was  exercisable  at such time),  by the
          estate of the  Employee  (or by the person or persons  who acquire the
          right to exercise the Option by written  designation  of the Employee)
          at any time within the period  ending ten (10) years after the Date of
          Grant,  at the end of which period the Option,  to the extent not then
          exercised, shall terminate and the estate or other beneficiaries shall
          forfeit all rights hereunder.  In no event, however, may the Option be
          exercised  after the  expiration  of the term  provided  in  Section 4
          hereof.

               (b) In the  event  that the  employment  of the  Employee  by the
          Company  and any parent or  subsidiary  corporation  of the Company is
          terminated  by  reason of the  Disability  (as  defined  below) of the
          Employee  on or after the first  date  upon  which he would  have been
          entitled  to exercise  the Option  under the  provisions  of Section 3
          hereof,  the Option may, subject to the provisions of Sections 5 and 8
          hereof,  be exercised with respect to all or any part of the shares of
          Common Stock as to which he had not  exercised  the Option at the time
          of his Disability  (but only to the extent the Option was  exercisable
          at such time) by the Employee, at any
<PAGE>
                                       3



          time within the period  ending ten (10) years after the Date of Grant,
          at the  end of  which  period  the  Option,  to the  extent  not  then
          exercised,  shall  terminate and the Employee shall forfeit all rights
          hereunder even if the Employee  subsequently  returns to the employ of
          the Company or any parent or subsidiary corporation of the Company. In
          no event, however, may the Option be exercised after the expiration of
          the term provided in Section 4 hereof. For purposes of this Agreement,
          "Disability"  shall have the same meaning as the term  "permanent  and
          total  disability" under Section 22(e)(3) of the Internal Revenue Code
          of 1986, as amended (the "Code").

                  e) The third sentence of Section 9 is hereby deleted such that
      Section 9 shall read in its entirety as follows:

               9.Merger  or  Consolidation,  Etc. of the  Company.  Upon (a) the
          merger  or   consolidation   of  the  Company  with  or  into  another
          corporation,  if the  agreement  of merger or  consolidation  does not
          provide  for  (i)  the  continuance  of  this  Option,   or  (ii)  the
          substitution  of new option(s) for this Option,  or for the assumption
          of such  Option by the  surviving  corporation,  (b) the  dissolution,
          liquidation, or sale of substantially all the assets of the Company or
          (c)  if  applicable  to the  Employee,  a  Change  in  Control  of the
          Corporation  (as defined  herein),  the Employee  shall have the right
          immediately prior to the effective date of such merger, consolidation,
          dissolution,  liquidation,  sale of assets or Change in Control of the
          Corporation,  to exercise this Option (to the extent not exercised and
          not  otherwise  expired  or  terminated)  in whole or in part  without
          regard to any  installment  provision  that may have been made part of
          the terms and  conditions of this Option.  The Company,  to the extent
          practicable, shall give advance notice to the Employee of such merger,
          consolidation,  dissolution,  liquidation, sale of assets or Change in
          Control of the  Corporation.  As used herein,  a "Change in Control of
          the  Corporation"  shall be  deemed  to have  occurred  if any  person
          (including any individual, firm, partnership or other entity) together
          with all Affiliates and Associates (as defined under Rule 12b-2 of the
          General  Rules  and  Regulations   promulgated  under  the  Securities
          Exchange Act of 1934, as amended) of such person,  but excluding (i) a
          trustee  or other  fiduciary  holding  securities  under  an  employee
          benefit plan of the Company or any  subsidiary of the Company,  (ii) a
          corporation owned, directly or indirectly,  by the stockholders of the
          Company in  substantially  the same  proportions as their ownership of
          the  Company,  (iii) the Company or any  subsidiary  of the Company or
          (iv) only as  provided  in the  immediately  following  sentence,  the
          Employee, together with all Affiliates and Associates of the Employee,
          is  or  becomes  the  Beneficial  Owner  (as  defined  in  Rule  13d-3
          promulgated  under the  Exchange  Act),  directly  or  indirectly,  of
          securities of the



<PAGE>
                                       4



          Company  representing  40% or more of the combined voting power of the
          Company's then outstanding  securities,  such person being hereinafter
          referred to as an Acquiring  Person.  The provisions of clause (iv) of
          the  immediately  preceding  sentence shall apply only with respect to
          the Option(s)  held by the Employee who,  together with his Affiliates
          or Associates, if any, is or becomes the direct or indirect Beneficial
          Owner of the percentage of securities set forth in such clause.

                  Except  as  previously  amended  and as  modified  above,  the
      Agreement  shall continue in full force and effect.  Please  indicate your
      agreement to the foregoing  amendment by executing the  acknowledgment  to
      this letter in the space provided below.

                                           Very truly yours,

                                           ICG HOLDINGS (CANADA), CO.
                                           (successor to IntelCom Group Inc. and
                                           ICG Holdings (Canada), Inc.)


                                           By: /s/ Don Teague
                                              ----------------------------------
                                              H. Don Teague, Executive Vice
                                              President


                                           ICG COMMUNICATIONS, INC.


                                           By: /s/ Don Teague
                                              ----------------------------------
                                              H. Don Teague, Executive Vice
                                              President

ACCEPTED AND AGREED TO AS OF
the 10th day of March, 1999.

/s/ J. Shelby Bryan
-----------------------------
J. Shelby Bryan