Horseshoe Reef wraps around the eastern and northern shores of Anegada, extending for kilometres and reaching depths that range from snorkellable shallows to 30-metre walls. It is one of the largest barrier reefs in the Caribbean, and over the centuries it has been one of the most dangerous — hundreds of ships lie on its floor, from Spanish galleons to 20th-century freighters.
Dive operators from Tortola and from Anegada itself run trips to the more accessible wreck sites, including the Paramatta, a 19th-century iron steamship. For snorkellers, the inshore sections near Loblolly Bay give access to healthy coral without requiring a boat. The reef's remoteness from the BVI's main charter fleet means the diving here is significantly less crowded than sites near Tortola.