Cranmore Tower is 45 metres (148 ft) tall. The tower was built in 1862-1864, by Thomas Henry Wyatt for John Moore Paget of Cranmore Hall (now part of All Hallows Preparatory School). There is a viewing area at the top with pair of semi-circular headed openings to each face with a restored iron-railed balcony beneath each pair. A similar balcony just over half-way up is continued right round the tower. It has been designated by English Heritage as a grade II listed building.
In World War II it was used as a lookout tower by the Home Guard and the Royal Corps of Signals but by 1984 the tower had fallen into disrepair and was sold to Donald Beaton who undertook repairs. During the course of the repairs the remains of a Roman fort with a hoard of coins was discovered adjacent to the tower. In 1988 it was sold again, this time to Nick Ridge who opened it to the public. The tower was then acquired by its current owner. Further restorations were carried out, including the installation of a new timber staircase to allow access to the balconies at the top of the tower at a height of 320 metres (1,050 ft) above sea level. From early 2008 the tower has been again open to the public. A small fee is usually charged to ascend the tower which is open on weekends, bank and school holidays and by arrangement.
Cranmore Tower is a Grade II National Hertigage Listed Building, first listed on the 16th January 1980 its List Entry Number is 1216763.