The island was created artificially when Penton Hook Lock was built, although before the lock was built, Thames waters would often flood across the neck of the "hook". Thus flow has been facilitated when the river is at its highest due to rainfall by the construction of the large weir at the midpoint of the long loop. The island is uninhabited, wooded and secluded, used for nature conservation purposes. Along one side is a backwater dug out to provide a fish refuge when the stream is strong and a fish spawning stream constructed in 1999. The island has many paths enabling visitors to see some of its wildlife. It particularly it caters for angling - permits can be obtained from the Environment Agency.