Exhibit 99.4

                        CROWN CASTLE INTERNATIONAL CORP.

                       Offer for any and all Outstanding
                          9 3/8% Senior Notes due 2011
                                in Exchange for
                    Registered 9 3/8% Senior Notes due 2011

To Our Clients:

  Enclosed for your consideration is a Prospectus, dated       , 2001 (the
"Prospectus"), and the enclosed Letter of Transmittal (the "Letter of
Transmittal"), relating to the offer (the "Exchange Offer") of Crown Castle
International Corp. (the "Company") to exchange its 9 3/8% Senior Notes due
2011, which have been registered under the Securities Act of 1933, as amended,
for its outstanding 9 3/8% Senior Notes due 2011 (the "Old Notes"), upon the
terms and subject to the conditions described in the Prospectus. The Exchange
Offer is being made in order to satisfy certain obligations of the Company
contained in the Registration Rights Agreement dated as of May 15, 2001 between
the Company and the initial purchasers referred to therein.

  This material is being forwarded to you as the beneficial owner of the Old
Notes carried by us in your account but not registered in your name. A tender
of such Old Notes may only be made by us as the holder of record and pursuant
to your instructions.

  Accordingly, we request instructions as to whether you wish us to tender on
your behalf the Old Notes held by us for your account, pursuant to the terms
and conditions set forth in the enclosed Prospectus and Letter of Transmittal.

  Your instructions should be forwarded to us as promptly as possible in order
to permit us to tender the Old Notes on your behalf in accordance with the
provisions of the Exchange Offer. The Exchange Offer will expire at 5:00 p.m.,
New York City time, on       , 2001 (the "Expiration Date") (20 business days
following the commencement of the Exchange Offer) unless extended by the
Company. Any Old Notes tendered pursuant to the Exchange Offer may be withdrawn
at any time before 5:00 p.m., New York City time, on the Expiration Date.

  Your attention is directed to the following:

  1. The Exchange Offer is for any and all Old Notes.

  2. The Exchange Offer is subject to certain conditions set forth in the
  Prospectus in the section captioned "The Exchange Offer--Conditions to the
  Exchange Offer."

  3. The Exchange Offer expires at 5:00 p.m., New York City time, on the
  Expiration Date, unless extended by the Company.

  If you wish to tender your Old Notes, please so instruct us by completing,
executing and returning to us the instruction form on the back of this letter.
The Letter of Transmittal is furnished to you for information only and may not
be used directly by you to tender Old Notes.


                          INSTRUCTIONS WITH RESPECT TO
                               THE EXCHANGE OFFER

  The undersigned acknowledge(s) receipt of your letter and the enclosed
material referred to therein relating to the Exchange Offer made by Crown
Castle International Corp. with respect to its Old Notes.

  This will instruct you to tender the Old Senior Notes or Old Senior Discount
Notes held by you for the account of the undersigned, upon and subject to terms
and conditions set forth in the Prospectus and the related Letter of
Transmittal.

  Please tender the Old Notes held by you for my account as indicated below:



                                             Aggregate Principal Amount
                                                of Old Senior Notes

                                   
9 3/8% Senior Notes due 2011.........
                                      ----------------------------------------

                                      (must be an integral multiple of $1,000)
[_] Please do not tender any Old
   Senior Notes held by you for my
   account.

Dated: , 2001
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                                                    Signature(s)

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                                             Please print name(s) here

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                                                    Address(es)

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                                        Area Code(s) and Telephone Number(s)

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                                            Tax Identification or Social
                                                  Security No(s).

  None of the Old Notes held by us for your account will be tendered unless we
receive written instructions from you to do so. Unless a specific contrary
instruction is given in the space provided, your signature(s) hereon shall
constitute an instruction to us to tender all the Old Notes held by us for your
account.