historical debate over this during the late 19th and early 20th centuries, the historian Henry Symonds argued that the first falls occurred during the 18th century, W. Norman placed the main fall in 1835, and T. Groves argued in favour of a more recent collapse in the second half of the 19th century. The ruined castle was drawn and painted by various artists in the 18th and 19th centuries, including Samuel Buck, J. H. Grimm, C. Sawyer and Edward Pritchard. The castle featured in Joseph Drew's short novel "the Poisoned Cup" in 1876. 20th–21st centuries In 1902, the Weymouth Corporation purchased the castle for the town from the Department of Woods and Forests for a total of £150. During the Second World War the castle housed an anti-aircraft battery as part of the defences created around Portland Harbour. Despite the construction of the Portland breakwaters nearby, the unstable clay cliffs remained vulnerable to erosion; in 1930 the ruins were closed to the public due to safety concerns and the remaining embrasure of the gun platform collapsed in the 1950s. In 2009, £23,100 was awarded by the Heritage Lottery Fund for an initial survey of the site, which by now had been placed on English Heritage's register of listed buildings at risk of decline, followed by a further £194,700 in 2011 for substantial repair work. As part of the work, a three-dimensional laser scan of the stonework was undertaken, and a steel and oak walkway was installed around the interior of the castle. The castle reopened to the public in 2012, and the following year it was removed from English Heritage's at risk register. The castle is protected under UK law as a grade II* listed building and as a scheduled monument. The castle was once again closed to the public in 2021 after vertical cracks on an internal wall were found to have widened. Permanent metal fencing now surrounds the castle preventing public access. Architecture Sandsfoot Castle was built from Portland stone with ashlar facings and a rubble core. It comprised a main blockhouse attached to an octagonal gun room, overlooking the sea. The two-storey blockhouse is across, with a gate-tower on its landward side. It probably originally had four rooms for the accommodation and cooking facilities for the garrison, with staircases leading up to the first floor and down into its basement. The gate-tower held a small room on