Brownsea Island Brownsea Island Brownsea Island (also archaically known as "Branksea") is the largest of the islands in Poole Harbour in the county of Dorset, England. The island is owned by the National Trust. Much of the island is open to the public and includes areas of woodland and heath with a wide variety of wildlife, together with cliff top views across Poole Harbour and the Isle of Purbeck. The island was the location of an experimental camp in 1907 that led to the formation of the Scout movement the following year. Access is by public ferry or private boat; in 2017
Brownsea Castle another device in 1544 to further improve the country's defences, particularly along the south coast. The castle was built on the south-east corner of Brownsea Island between 1545 and 1547 to protect the entrance of the busy Poole Harbour. The island belonged to the Crown, having been confiscated from Cerne Abbey during the Dissolution of the Monasteries a few years before. It was a conservative design, being a one-storey, square blockhouse, reported in 1552 to be across, able to support guns on its roof and sub-divided into three rooms; the blockhouse was originally intended to have been two storeys in