EXHIBIT 21
CROWN CASTLE INTERNATIONAL CORP. SUBSIDIARIES
| Subsidiary | Jurisdiction of Incorporation | |
| CC FN Holdings LLC | Delaware | |
| CC Holdings GS V LLC | Delaware | |
| CC Sunesys Fiber Networks LLC | Delaware | |
| CC Towers Guarantor LLC | Delaware | |
| CC Towers Holding LLC | Delaware | |
| CCATT LLC | Delaware | |
| CCATT Holdings LLC | Delaware | |
| CCGS Holdings Corp. | Delaware | |
| CCT2 Holdings LLC | Delaware | |
| CCTM1 LLC | Delaware | |
| CCTM Holdings LLC | Delaware | |
| CCTMO LLC | Delaware | |
| Crown Atlantic Company LLC | Delaware | |
| Crown Castle Atlantic LLC | Delaware | |
| Crown Castle CA Corp. | Delaware | |
| Crown Castle BP ATT LLC | Delaware | |
| Crown Castle GT Company LLC | Delaware | |
| Crown Castle GT Corp. | Delaware | |
| Crown Castle GT Holding Sub LLC | Delaware | |
| Crown Castle International Corp. de Puerto Rico | Puerto Rico | |
| Crown Castle Investment Corp. | Delaware | |
| Crown Castle Investment II Corp. | Delaware | |
| Crown Castle NG Central LLC | Delaware | |
| Crown Castle NG East LLC | Delaware | |
| Crown Castle NG Networks LLC | Delaware | |
| Crown Castle NG West LLC | Delaware | |
| Crown Castle Operating Company | Delaware | |
| Crown Castle PT Inc. | Delaware | |
| Crown Castle PR LLC | Puerto Rico | |
| Crown Castle Solutions LLC | Delaware | |
| Crown Castle South LLC | Delaware | |
| Crown Castle Towers 06-2 LLC | Delaware | |
| Crown Castle Towers LLC | Delaware | |
| Crown Castle USA Inc. | Pennsylvania | |
| Crown Communication LLC | Delaware | |
| Fibernet Direct Holdings LLC | Delaware | |
| Fibernet Direct Texas LLC | Delaware | |
| Fibernet Direct TEL LLC | Delaware | |
| Fibernet Direct Florida LLC | Delaware | |
| Fibertech Holdings Corp. | Delaware | |
| Fibertech Networks, LLC | Delaware | |
| Fiber Technologies Networks, L.L.C. | New York | |
| Global Signal Acquisitions LLC | Delaware | |
| Global Signal Acquisitions II LLC | Delaware | |
| Global Signal Acquisitions III LLC | Delaware | |
| Global Signal Acquisitions IV LLC | Delaware | |
| Global Signal GP LLC | Delaware | |
| Global Signal Holdings III LLC | Delaware | |
| Global Signal Operating Partnership, L.P. | Delaware | |
| GoldenState Towers, LLC | Delaware | |
| InfraSource FI, LLC | Delaware | |
| Light Tower Clearinghouse LLC | Delaware | |
| Lightower Fiber Networks I, LLC | Delaware | |
| Lightower Fiber Networks II, LLC | New York | |
| Light Tower Holdings LLC | Delaware | |
| LTS Buyer LLC | Delaware | |
| LTS Group Holdings LLC | Delaware | |
| LTS Intermediate Holdings A LLC | Delaware | |
| LTS Intermediate Holdings B LLC | Delaware | |
| LTS Intermediate Holdings C LLC | Delaware | |
| MW Cell REIT 1 LLC | Delaware | |
| OP LLC | Delaware | |
| Pinnacle Towers Acquisition LLC | Delaware | |
| Pinnacle Towers Acquisition Holdings LLC | Delaware | |
| Pinnacle Towers LLC | Delaware | |
| PR Site Development Corporation | Delaware | |
| WCP Wireless Site RE Funding LLC | Delaware | |
| WCP Wireless Site RE Holdco LLC | Delaware | |
| Sunesys, LLC | Delaware | |
| Towers Development Corporation | Maryland | |
| Towers Ventures III, LLC | Tennessee | |
| Sidera Networks, Inc. | Delaware | |
| Wilcon Holdings LLC | Delaware | |
| Yankee Metro Parent, Inc. | Delaware | |