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 May 30, 1995 (the "Agreement"),  which grants Mr. Bryan an option to
purchase an aggregate  1,550,000 Common Shares,  no par value, of the Company at
$7.9375 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.

     The Company, ICG and Mr. Bryan hereby further amend Sections 4, 6, and 7 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) The first  paragraph  of Section 4 shall read in its  entirety  as
              follows:

          4. Term of  Option.  The term of the  Option  shall be a period of ten
     (10)  years  from the Date of Grant,  subject  to  earlier  termination  or
     cancellation as provided in this Agreement.

          b) The first  paragraph  of  Section 6 shall read in its  entirety  as
             follows:
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                                       2


          If the Employee ceases to be employed by the Company and or any parent
     or  subsidiaries  by  reason  of his  discharge  for Cause (as such term is
     defined in the Employment Agreement,  dated as of May 30, 1995, between the
     Company and the Employee  (the  "Employment  Agreement")),  the Option will
     forthwith terminate.  If, however, the Employee for any other reason ceases
     to be so  employed,  or there exists a Change of Control of the Company (as
     such term is  defined  in the  Employment  Agreement),  whether  or not the
     Employee's employment is so terminated, the Option shall automatically vest
     in full and may be exercised in full,  at any time within the term provided
     in  Section  4  thereof,  at the  end of  which  period  the  Option  shall
     terminate.  Notwithstanding  the  foregoing or any other  provision of this
     Agreement,  in the event of a conflict  between the terms of this Agreement
     and the terms of the Employment  Agreement regarding the Option,  including
     without limitation,  terms with respect to vesting and exercise,  the terms
     of the Employment Agreement shall govern and be controlling.

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

          7. Exercise Upon Death; Disability.  (a) If the Employee dies while he
     is employed  by the  Company or any  subsidiary  thereof  within  three (3)
     months after he has ceased to be an employee  (provided  such cessation was
     not due to the Employee  having been  discharged  for Cause),  during which
     period  he would  have been  entitled  to  exercise  the  Option  under the
     provisions of Section 6 hereof,  the Option may,  subject to the provisions
     of Section 5 hereof,  be exercised,  to the extent the Employee  would have
     been entitled under Section 3 hereof to exercise the Option on the day next
     preceding  the date of his death,  by the estate of the  Employee or by any
     person  who  acquired  the  right to  exercise  the  Option by  bequest  or
     inheritance  at any time within the period  ending ten (10) years after the
     Date of Grant,  at the end of which period the Option shall  terminate.  In
     any event, the Option may not 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 or
     any subsidiary thereof is terminated by reason of the "disability" (as such
     is defined in the  Employment  Agreement) of the Employee,  the Option may,
     subject to the provisions of Section 5 hereof, be exercised,  to the extent
     the Employee
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                                       3


     would have been  entitled  under Section 3 hereof to exercise the Option on
     the day  next  preceding  the  date of the  termination  of the  Employee's
     employment,  at any time within the period  ending ten (10) years after the
     Date of Grant,  at the end of which period the Option shall  terminate.  In
     any event, the Option may not be exercised after the expiration of the term
     provided in Section 4 hereof.

     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