Eastwater Cavern is a cave near Priddy in the limestone of the Mendip Hills, in Somerset, England.

[3] It was first excavated in April 1902 by a team led by Herbert E. Balch composed of paid labourers and volunteers from the Wells Natural History Society.

Progress was initially slow, but by February 1903 Balch and Willcox had discovered substantial passage, following the streamway down to the bottom of the cave.

[4] On 28 August 1910 severe flooding rendered the boulder ruckles unstable, and the bottom of the cave was not reached again for another three years.

[6] Dolphin ladder pitch also suffered a rock fall and was blocked by a sofa-sized boulder in 1959,[7] but the route was re-opened in 1966.