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                                                                    EXHIBIT 99.1

                            Certification Pursuant to
                             18 U.S.C. Section 1350
      As Adopted Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002

In connection with the Annual Report on Form 10-K of Crown Castle International
Corp., a Delaware Corporation (the "Company"), for the period ending December
31, 2002 as filed with the Securities and Exchange Commission on the date hereof
(the "Report"), each of the undersigned officers of the Company hereby certifies
pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the
Sarbanes-Oxley Act of 2002, that to the best of such officer's knowledge:

     1)   the Report complies with the requirements of Section 13(a) or 15(d) of
          the Securities Exchange Act of 1934; and

     2)   the information contained in the Report fairly presents, in all
          material respects, the financial condition and results of operations
          of the Company as of December 31, 2002 (the last date of the period
          covered by the Report).

                                       /s/ John P. Kelly
                                       -----------------------------------
                                       John P. Kelly
                                       President and Chief Executive Officer
                                       March 26, 2003

                                       /s/ W. Benjamin Moreland
                                       -----------------------------------
                                       W. Benjamin Moreland
                                       Senior Vice President,
                                       Chief Financial Officer and Treasurer
                                       March 26, 2003

     A signed original of this written statement required by Section 906 has
been provided to Crown Castle International Corp. and will be retained by Crown
Castle International Corp. and furnished to the Securities and Exchange
Commission or its staff upon request.

