Battery Rocks (grid reference SW477298) are a rocky headland situated to the south of the harbour of Penzance, Cornwall, England, UK.
The rocks take their name from a gun battery that was situated there from 1740, following a petition by Penzance Borough council for protection from French naval attacks. The rocks are the setting for the Penzance war memorial and the restored Grade II Listed Jubilee Pool, an art deco lido, one of the very few surviving and described in the listing notes as one of the finest examples. People swim from the rocks daily throughout the year.
Battery Rocks and the adjacent tidal beach, a favourite local spot, are an integral part of the Pen Sans--Holy Headland--after which Penzance is named. Battery Rocks have been a favourite location for local swimmers for as long as can be remembered, even at the heart of winter!
The rocks are on the northern shore of Mount's Bay, and alongwith the headland, provide shelter for Penzance harbour from the prevailing south-west winds. A rock on the most easterly point is called Carn Olven and on the western side are the Chimney Rocks. Four thousand years ago the sea-level was lower and either side of Battery Rocks, on the beaches at Ponsandane (to the east) and Wherrytown (west), evidence of a ′submerged forest′ can be seen at low tide in the form of several partially fossilised tree trunks. Artefacts dating from the Mesolithic (10,000 to 5,000 BCE) have been found indicating some occupation contemporary with the forest. The submerged forest in the intertidal area between Wherrytown and Long Rock is of national importance and is a Cornwall Geology Site.
They are also home to a variety of wildlife including a colony of rare purple sandpiper (Calidris maritima) which shows a preference for rocky shores. Most of the sandpipers wintering in Cornwall are probably from the Canadian arctic and the rejection of the proposed development of Penzance harbour (see below), reduced the threat to the local flock.