THIRD AMENDMENT TO LEASE



         THIS THIRD  AMENDMENT  TO LEASE (the  "Amendment")  is made and entered
into this ______ day of , 1996, by and between THE PRUDENTIAL  INSURANCE COMPANY
OF AMERICA ("Landlord"),  having an address at One Prudential Plaza, Suite 1200,
Chicago,  Illinois, 60601, and DATA TRANSMISSION NETWORK CORPORATION ("Tenant"),
having an office at 9110 West Dodge Road, Suite 200, Omaha, Nebraska 68114.


                                    RECITALS

A.       The  Prudential  Insurance  Company  of America  and Data  Transmission
         Network  Corporation entered into that certain Lease dated as of May 2,
         1995, for Suites #175A, #110, #200, #300, #301, #310, #320, #325, #340,
         #360, and #362  containing  75,931 rentable square feet in the Building
         known as  Embassy  Plaza,  located  at 9110  West  Dodge  Road,  Omaha,
         Nebraska ("the Premises").

B.       Subsequently,  The  Prudential  Insurance  Company Of America  and Data
         Transmission  Network  Corporation  executed a First Amendment To Lease
         dated  September  29,  1995,  and a Second  Amendment  To  Lease  dated
         November  30,  1995.  The  combined  terms of the Lease and  subsequent
         Amendments shall herein be referred to as the "Lease".

C.       All  capitalized  terms not  defined  herein  shall  have the  meanings
         ascribed to them in the Lease.

         NOW,  THEREFORE,  in consideration of the foregoing  promises and other
good and  valuable  considerations,  the  receipt and  sufficiency  of which are
hereby acknowledged, the parties hereto covenant and agree as follows:

1.       Term. The  Commencement  Date of the Lease,  with respect to Space "B",
         shall be revised to be that period of time commencing  February 5, 1996
         and ending on May 31, 2005, (the "Expiration Date").

2.       Base Rent. Paragraph 3 of the First Amendment To Lease shall be revised
         to read:  Tenant  shall pay as Base Rent with  respect to Space "A" and
         Space "B", the sum of Nine Hundred Twenty-Six  Thousand,  Forty Dollars
         and Four Cents ($926,040.04) payable monthly as follows:

                  October 1, 1995 - January 31, 1996  $4,533.17 / Month Feburary
                  1, 1996 - February 29, 1996  $7,816.69 / Month March 1, 1996 -
                  June 30,  1996  $8,342.05  / Month July 1, 1996 - May 31, 2005
                  $8,100.21 / Month

3.       Adjustment Rent. With respect to the Space "B", Effective July 1, 1996,
         Tenant  shall  pay  Adjustment  Rent in  accordance  with the terms and
         conditions contained in Paragraph 2 of the Lease.

4.       Effect of Agreement.  Except as herein specifically provided, the terms
         and conditions of the Lease shall continue in full force and effect.



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5.       This  Amendment  shall be binding  upon and inure to the benefit of the
         parties hereto, their successors and assigns.

6.       The  parties   hereto  hereby   reaffirm  and  ratify  all   covenants,
         representations  and  warranties  in  the  Lease  as  amended  by  this
         Amendment.



         IN WITNESS WHEREOF, Landlord and Tenant have executed this Amendment as
of the day and year first above written.


Tenant:                                      Landlord:

Data Transmission Network Corporation,       The Prudential Insurance Company of
a Delaware corporation                       America, a New Jersey corporation


                                             By:  Pacific Realty Group, Inc.,
By:                                               its Managing Agent


Its:                                         By:


                                            Its:



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