Exhibit 99.1

FOR IMMEDIATE RELEASE

CROWN CASTLE INTERNATIONAL

ANNOUNCES FIRST QUARTER 2008 RESULTS AND

CEO AND CFO SUCCESSION PLAN

April 23, 2008 – HOUSTON, TEXAS – Crown Castle International Corp. (NYSE:CCI) today reported results for the quarter ended March 31, 2008 and announced that the Board of Directors has approved a succession plan for its Chief Executive Officer and Chief Financial Officer. Effective July 1, 2008, Ben Moreland, currently Crown Castle’s Executive Vice President and Chief Financial Officer, will become Crown Castle’s President and Chief Executive Officer; and Jay Brown, currently Crown Castle’s Vice President and Treasurer, will become Crown Castle’s Senior Vice President and Chief Financial Officer. John Kelly, currently Crown Castle’s President and Chief Executive Officer, will remain in an executive position as Executive Vice-Chairman of the Board of Directors.

“We had a very good first quarter 2008, exceeding our estimates for site rental revenue, site rental gross margin, Adjusted EBITDA and recurring cash flow,” stated Mr. Kelly. “The year over year growth in recurring cash flow per share of 40% that we achieved in the first quarter of 2008, as compared to the first quarter of 2007, demonstrates the significant growth that we are able to deliver with our tower portfolio and capital structure. During the first quarter of 2008, we completed the few remaining integration items related to our acquisition of Global Signal last year. We are encouraged by our year to date results, as reflected in our increase to full year 2008 Outlook. Further, with the successful conclusion of the 700 MHz auction and the accelerating growth in wireless data services, I remain excited about the long-term opportunities for our business.”

CONSOLIDATED FINANCIAL RESULTS

On January 12, 2007, Global Signal Inc. merged into a subsidiary of Crown Castle (“Merger”). The results of the former subsidiaries of Global Signal Inc. (“Global Signal”) are included in Crown Castle’s results from January 12, 2007.

Site rental revenue for the first quarter of 2008 increased $45.2 million, or 15%, to $345.0 million from $299.8 million for the same period in the prior year. Site rental gross margin, defined as site rental revenue less site rental cost of operations, increased 20% to $232.7 million, up $39.5 million in the first quarter of 2008 from the same period in 2007. Adjusted EBITDA for the first quarter of 2008 increased $43.7 million, or 26%, to $211.0 million, up from $167.3 million for the same period in 2007.

Recurring cash flow, defined as Adjusted EBITDA less interest expense less sustaining capital expenditures, increased from $82.4 million in the first quarter of 2007 to $118.1 million for the first quarter of 2008, up 43%. Weighted average common shares outstanding was 279.3 million for the first quarter of 2008 as compared to 273.5 million for the same period in the prior year. Recurring cash flow per share, defined as recurring cash flow divided by weighted average common shares outstanding, increased 40% to $0.42 in the first quarter of 2008, compared to $0.30 in the first quarter of 2007.

Net loss was $13.2 million for the first quarter of 2008, compared to a net loss of $42.9 million for the same period in 2007. Net loss after deduction of dividends on preferred stock was $18.4 million in the first quarter of 2008, compared to a loss of $48.1 million for the same period in 2007. First quarter 2008 net loss (after deduction of dividends on preferred stock) per share was $0.07, compared to a net loss per share of $0.18 in the first quarter of 2007.

SUCCESSION PLANS FOR CEO AND CFO

As approved by Crown Castle’s Board of Directors, effective July 1, 2008, Mr. Moreland will become Crown Castle’s President and Chief Executive Officer. Mr. Kelly will remain in an executive position as Executive Vice-Chairman of the Board of Directors with principal responsibility for overseeing Crown Castle’s strategy and ensuring leadership continuity. Also effective July 1, 2008, Mr. Brown will become Crown Castle’s Senior Vice President and Chief Financial Officer. J. Landis Martin will remain Chairman of the Board of Directors.

“The Board of Directors has been carefully evaluating our management succession plans and is extremely pleased with the depth of the management team that Mr. Kelly has built over the

years,” stated Mr. Martin. “Crown Castle is well-positioned to continue our record of success under the leadership of Ben Moreland. Both Mr. Moreland and Mr. Brown have been instrumental in the development and success of Crown Castle, and our Board of Directors is unanimous in our belief that their leadership will continue to deliver significant value to our stockholders.”

“Our company has never been stronger operationally or financially,” stated Mr. Kelly. “I am confident that our executive management team, under Ben’s leadership, will take our company to new heights. I look forward to ensuring that a smooth transition of responsibilities occurs and to working with Ben on overall strategy as we capitalize on the strong wireless industry fundamentals.”

“I have benefited greatly from John Kelly’s leadership and guidance over the last eight years,” stated Mr. Moreland. “I am excited to lead our experienced management team and this great organization in continuing Crown Castle’s consistent track record of delivering for our employees, customers and stockholders.”

Mr. Moreland was appointed Chief Financial Officer of Crown Castle in April 2000. Prior to that, he served as Senior Vice President and Treasurer of Crown Castle and its domestic subsidiaries from October 1999. He was appointed to the Board of Directors in August 2006. Mr. Brown was appointed Treasurer of Crown Castle in May 2004 and Vice President of Finance in August 2001. Since joining Crown Castle in August of 1999, Mr. Brown has served in a number of positions in corporate development and corporate finance.

SEGMENT RESULTS

US site rental revenue for the first quarter of 2008 increased $39.0 million, or 14%, to $323.7 million, compared to first quarter 2007 US site rental revenue of $284.8 million. US site rental gross margin increased 19% to $217.3 million, up $34.4 million in the first quarter of 2008 from the same period in 2007.

Australia site rental revenue for the first quarter of 2008 increased $6.2 million, or 42%, to $21.3 million, compared to $15.0 million for the first quarter of 2007. Australia site rental gross margin for the first quarter of 2008 increased $5.0 million, or 49%, to $15.3 million, compared to first quarter 2007 site rental gross margin of $10.3 million. In prior years, Crown Castle has benefited from an annual customer payment in the second quarter. This benefit to site rental revenue and site rental gross margin of $2.7 million was achieved in the first quarter of 2008 and, as such, was not included in our previously provided first quarter 2008 Outlook.

INVESTMENTS AND LIQUIDITY

During the first quarter of 2008, Crown Castle invested $61.7 million in capital expenditures, comprised of $3.8 million of sustaining capital expenditures and $57.9 million of revenue generating capital expenditures, of which $16.9 million was spent on existing sites, $27.0 million on land purchases and $14.0 million on the construction of new sites, including the completion of nine towers, and the acquisition of ten towers.

During the first quarter of 2008, Crown Castle purchased 1.1 million of its outstanding common shares for $42 million at an average price of $36.99 per share. Since January 2003, Crown Castle has invested over $2.2 billion in purchases of its securities to reduce fully diluted common shares by 88 million, or 29%.

In January 2008, Crown Castle borrowed $75 million under its revolving credit facility. As of April 23, 2008, Crown Castle has $100 million of undrawn capacity under its revolving credit facility.

“During the first quarter of 2008, we invested over $100 million in our core tower business including purchases of our own shares,” stated Mr. Moreland. “Consistent with our past actions, we have continued to evaluate and invest in share repurchases, construction of new sites, tower acquisitions and land purchases, which we believe will be long-term accretive to our business. This strategy, along with strong operating results and an appropriate capital structure, has resulted in a 40% growth in recurring cash flow per share in the first quarter of 2008. As presented in the Outlook table below, our 2008 Outlook suggests continued growth in recurring cash flow per share above our targeted 20% to 25% growth per year.”

OUTLOOK

The following Outlook tables are based on current expectations and assumptions. The Outlook tables assume a US dollar to Australian dollar exchange rate of 0.89 US dollars to 1.00 Australian dollar for full year 2008 Outlook.

As reflected in the following tables, Crown Castle has increased the midpoint of its full year 2008 Outlook, previously issued on February 6, 2008, for site rental revenue by $10.5 million, site rental gross margin by $10.0 million, Adjusted EBITDA by $7.0 million and recurring cash flow by $7.0 million.

This Outlook section contains forward-looking statements, and actual results may differ materially. Information regarding potential risks which could cause actual results to differ from the forward-looking statements herein is set forth below and in Crown Castle’s filings with the Securities and Exchange Commission (“SEC”).

The following table sets forth Crown Castle’s current Outlook for the second quarter of 2008 and full year 2008:

CONFERENCE CALL DETAILS

Crown Castle has scheduled a conference call for Thursday, April 24, 2008, at 10:30 a.m. eastern time to discuss first quarter 2008 results and Crown Castle’s Outlook. Please dial 303-262-2175 and ask for the Crown Castle call at least 10 minutes prior to the start time. A telephonic replay of the conference call will be available from 12:30 p.m. eastern time on Thursday, April 24, 2008 through 11:59 p.m. eastern time on Thursday, May 1, 2008 and may be accessed by dialing 303-590-3000 using passcode 11112200#. An audio archive will also be available on Crown Castle’s website at http://www.crowncastle.com shortly after the call and will be accessible for approximately 90 days.

Crown Castle engineers, deploys, owns and operates technologically advanced shared wireless infrastructure, including extensive networks of towers. Crown Castle offers significant wireless communications coverage to 91 of the top 100 US markets and to substantially all of the Australian population. Crown Castle owns, operates and manages over 22,000 and over 1,400 wireless communication sites in the US and Australia, respectively. For more information on Crown Castle, please visit http://www.crowncastle.com.

Summary of Non-Cash Amounts in Tower Gross Margin

In accordance with applicable accounting standards, Crown Castle recognizes site rental revenues and ground lease expenses monthly on a straight-line basis, regardless of whether the receipts and payments are in equal monthly amounts. An agreement, related to an acquisition in Australia, provides the seller with a rent-free period at the beginning of the lease term, and other agreements call for rent to be prepaid for a specified period. If, and to the extent the payment terms call for fixed escalations (as in fixed dollar or fixed percentage increases), the effect of such increases is recognized on a straight-line basis over the appropriate lease term. As a result of this accounting method, a portion of the revenue and expense recognized in a given period represents cash collected or paid in other periods.

A summary of the non-cash portions of our site rental revenue, ground lease expense, stock-based compensation for those employees directly related to US tower operations, net amortization of below-market and above-market lease acquired, and resulting impact on site rental gross margins is as follows:

Non-GAAP Financial Measures

This press release includes presentations of Adjusted EBITDA and recurring cash flow, which are non-GAAP financial measures.

Crown Castle defines Adjusted EBITDA as net income (loss) plus restructuring charges (credits), asset write-down charges, integration costs, depreciation, amortization and accretion, losses on purchases and redemptions of debt, interest and other income (expense), interest expense and amortization of deferred financing costs, impairment of available-for-sale securities, benefit (provision) for income taxes, minority interests, cumulative effect of change in accounting principle, income (loss) from discontinued operations, and stock-based compensation charges. Adjusted EBITDA is not intended as an alternative measure of cash flow from operations or operating results (as determined in accordance with Generally Accepted Accounting Principles (“GAAP”)).

Crown Castle defines recurring cash flow to be Adjusted EBITDA, less interest expense and less sustaining capital expenditures. Each of the amounts included in the calculation of recurring cash flow are computed in accordance with GAAP, with the exception of sustaining capital expenditures, which is not defined under GAAP. We define sustaining capital expenditures as capital expenditures (determined in accordance with GAAP) which do not increase the capacity or life of our revenue generating assets and include capitalized costs related to (i) maintenance activities on our towers, (ii) vehicles, (iii) information technology equipment, and (iv) office equipment. Recurring cash flow is not intended as an alternative measure of cash flow from operations or operating results (as determined in accordance with GAAP).

Adjusted EBITDA and recurring cash flow are presented as additional information because management believes these measures are useful indicators of the financial performance of our core businesses. In addition, Adjusted EBITDA is a measure of current financial performance used in our debt covenant calculations. Our measures of Adjusted EBITDA and recurring cash flow may not be comparable to similarly titled measures of other companies, including companies in the tower industry and in the historical financial statements of Global Signal. The tables set forth below reconcile these non-GAAP financial measures to comparable GAAP financial measures.

Reconciliations of Non-GAAP Financial Measures to Comparable GAAP Financial Measures:

Adjusted EBITDA, recurring cash flow and recurring cash flow per share for the quarters ended March 31, 2008 and 2007 are computed as follows:

Adjusted EBITDA and recurring cash flow for the quarter ending June 30, 2008 and the year ending December 31, 2008 are forecasted as follows:

Other Calculations:

Sustaining capital expenditures for the quarters ended March 31, 2008 and March 31, 2007 is computed as follows:

Site rental gross margin for the quarter ending June 30, 2008 and for the year ending December 31, 2008 is forecasted as follows:

Cautionary Language Regarding Forward-Looking Statements

This press release contains forward-looking statements and information that are based on our management’s current expectations. Such statements include, but are not limited to, plans, projections, Outlook and estimates regarding (i) long-term opportunities for our business, (ii) our future results, including as compared to historical results, following and based upon the management changes described in the press release, (iii) our operational and financial strength, (iv) recurring cash flow (including recurring cash flow per share and annual growth), (v) the impact of and return on our investments, including the purchase of our securities, land purchases, and the construction and acquisition of towers, (vi) currency exchange rates, (vii) site rental revenues, (viii) site rental cost of operations, (ix) site rental gross margin, (x) Adjusted EBITDA, (xi) interest expense and amortization of deferred financing costs, (xii) sustaining capital expenditures, (xiii) net loss (including net loss per share), and (xiv) the utility of certain financial measures in analyzing our results. Such forward-looking statements are subject to certain risks, uncertainties and assumptions, including but not limited to prevailing market conditions and the following:

Should one or more of these or other risks or uncertainties materialize, or should underlying assumptions prove incorrect, actual results may vary materially from those expected. More information about potential risk factors which could affect our results is included in our filings with the SEC.

		CROWN CASTLE INTERNATIONAL CORP. CONDENSED CONSOLIDATED STATEMENT OF OPERATIONS (UNAUDITED) AND OTHER FINANCIAL DATA (in thousands, except per share data)

		CROWN CASTLE INTERNATIONAL CORP. CONDENSED CONSOLIDATED BALANCE SHEET (UNAUDITED) (in thousands)

		CROWN CASTLE INTERNATIONAL CORP. CONDENSED CONSOLIDATED STATEMENT OF CASH FLOWS (UNAUDITED) (in thousands)

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CROWN CASTLE INTERNATIONAL CORP.

Summary Fact Sheet

(dollars in thousands)

Reconciliation of Non-GAAP Financial Measure (Adjusted EBITDA) to GAAP Financial Measure:

(dollars in thousands)

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CCI FACT SHEET Q1 2007 to Q1 2008

dollars in thousands