Seymour Tower, Coastal defence tower on a tidal island, Jersey

Seymour Tower is a square granite structure positioned on a rocky tidal island roughly 2 kilometers from Jersey's southeast coast. The solid stone construction offers views across the coastline and surrounding waters from its upper levels.

Built in 1782 under Sir Henry Seymour Conway's direction, the structure was part of a broader defensive network following a 1781 attack on Jersey. Its construction represented a strategic response to reinforce the island's maritime protection.

The tower's name comes from Field Marshal Henry Seymour Conway, who ordered Jersey's coastal towers after the 1781 Battle of Jersey. In 2012 it appeared in the BBC documentary Coast, in the episode "The Riddle of the Tides". Since 2006 Jersey Heritage has let it for self-catering stays.

The tower can be reached on foot at low tide, but the tide returns very quickly, so time the walk carefully. Facilities are minimal: there is some electricity but no running water. Guests must carry out all waste, including bagged toilet waste, and overnight stays require your own sleeping bag and a registered guide.

In May 2022 the tower housed a team led by Dr Matthew Pope of UCL's Institute of Archaeology, surveying the Violet Bank reef, where about 10 km2 of seabed is exposed at low spring tide. The work recorded further traces of Neanderthal activity, complementing finds at La Cotte de St Brelade dated between 250,000 and 50,000 years ago.