The area was formerly the site of Hounslow Gunpowder Works, and the island was created to contain a mill pool to drive mill machinery. Some remains of it can still be seen, but the only major surviving structure is the Shot Tower, built in 1828. There were frequent explosions, and the Shot Tower was probably built as a watch tower to warn workers of fire hazards. In 1927 the licence to manufacture gunpowder was withdrawn, and part of the site was sold to Twickenham Council. The Council turned it into Crane Park, which opened in 1935. In 1990 Crane Park Island was designated a Local Nature Reserve.