Crown Castle is a real estate investment trust. Co. owns, operates and leases shared communications infrastructure that is geographically dispersed throughout the U.S., including the towers and other structures, such as rooftops (collectively, towers), and the route miles of fiber primarily supporting small cell networks (small cells) and fiber solutions. Co. refers to its towers, fiber and small cells assets collectively as communications infrastructure. Co.'s primary business is providing access, including space or capacity, to its shared communications infrastructure via long-term contracts in various forms, including lease, license, sublease and service agreements.