Betchworth Castle is a mostly crumbled ruin of a fortified medieval stone house with some tall, two-storey corners strengthened in the 18th century, in the north of the semi-rural parish of Brockham. It is built on a sandstone spur overlooking the western bank of the Mole in Surrey in England. The ruin is a Scheduled Ancient Monument and is in the lowest category of listed architecture, Grade II, due east of Dorking railway station in Dorking and due west of Reigate. Although close to the river and edge of the course it is surrounded by "Betchworth Park" Golf Course named after the village east.