[1] Although known as an obelisk, the structure is in fact a square tower, made of red bricks on a stone base.

[3] The tower is situated on top of a hill, about 2 miles (3.2 km) east of Norris' house in Hawley.

[2] In 1812, the Royal Military College was established at Sandhurst on the other side of the turnpike road, and a settlement known as Cambridge Town (later becoming Camberley) grew up in the area to the west of the tower.

[2] It is not known why Norris built the tower, although a number of theories have been advanced, including that it was a watchtower guarding against highwaymen on the nearby road; that it was a beacon guiding travellers on the heath to safety; that it was a viewing platform for watching the local foxhunt; that it was a signalling tower; or that it was simply a folly with no purpose.

Various reasons have been put forward to explain why Dashwood and Norris needed to signal information between themselves.

It has even been suggested that they were involved in an espionage network, and that during the period of the American War of Independence Norris passed secret information to Dashwood, who was Postmaster General from 1765 to 1781.

This theory is supported by a letter written by Norris, dated 3 June 1778, in which he notes: "Did this day heliograph intelligence from Dr Franklin in Paris to Wycombe".