Arqiva is a telecommunications company which provides infrastructure and broadcast transmission facilities in the United Kingdom and Republic of Ireland. The present company was formed by National Grid Wireless (originally the UK subsidiary of Crown Castle) combining with Arqiva (formerly NTL Broadcast) in September 2008. Its main customers are broadcasters and mobile phone network operators, and its main asset is a network of over 1,000 radio and television transmission sites. It has been owned by the Australian investment house Macquarie Bank since 2004. Arqiva's headquarters are located in Crawley, Hampshire