The Folly Tower is a three-storey tower near the eastern edge of the park. Originally constructed by John Hanbury in 1762, it was demolished during the Second World War, after fears that it would act as a marker for German aircraft. The present tower is a replica, constructed in 1994. A short distance from this folly is the Shell Grotto. Designed by S. Gunston Tit, the structure was commissioned by Capel Hanbury Leigh and built in the 1830s. The garden historian Elisabeth Whittle describes the grotto as a "magnificant survivor". The interior is decorated with shells and bones, reputedly the work of Hanbury Leigh's first wife, Molly Mackworth. Both sites are open to the public at weekends from May to September. Restored in the 1990s, the grotto is a Grade II* listed building.