Bonteheuwel trig beacon
The first trigonometric beacons in South Africa were in Cape Town (See Maclears beacon) and they were based on star observations and precisely measured baselines.
Between 1833 and 1870 Thomas Maclear and Sir David Gill were given the task of verifying the size and shape of the earth in the Southern Hemisphere. They were to provide geodetic control for topographic maps and navigation charts.
The network was extended to eventually cover the whole country. Eventually, there were about 29000 highly visible trigonometric beacons on mountains, high buildings and water towers. There is a broken trig beacon on Bont Hill in Bonteheuwel. The Bont hill was a sand dune and sand mining during the construction of the apartheid scheme of the Bonteheuwel housing project was used in the construction of the the concrete trig beacon.
