Queen Adelaides Chapel

Queen Adelaide's Chapel, also known as the Grotto, is an eyecatcher built in 1827-28 to commemorate the visit of William IV to Mount Edgcumbe. The chapel is situated on the edge of a cliff and is partly carved out of solid rock. It features slatestone rubble walls with granite dressings and a slate roof. The building has an irregular plan, with a tunnel entrance on the left and a three-sided chamber on the right, each side having its own gabled roof. The interior includes a triangular recess at the rear, also carved from the cliff.

The picturesque Gothic style is evident in the tunnel, which has a four-centre arched entrance on the left side. The tunnel is two bays long, divided by a buttress, and features a diagonal buttress at the left end, with a string course above the buttresses and an embattled parapet. The chamber on the right has three splayed bays at the front, each with a four-centred arched opening. The central arch is of plain granite order, while the outer arches are of two orders. Each arch is supported by slatestone relieving arches and swept buttresses on either side, topped with small granite obelisk finials, although one obelisk to the right of the central arch is missing. Each arch has a coped gable above it, and the wall returns to the rear right, also embattled.

Inside, both the tunnel and the chamber have stone vaulted roofs. At the back of the chamber, the triangular recess in the rock includes a bench carved from the rock, with sockets remaining for fixing wooden seating. The chapel is part of Mount Edgcumbe Country Park.