Signal Hill, which is approximately 1148 feet high, lies next to Lion's Head and Table Mountain in Cape Town, South Africa. This hill used to be known as "Lion's Rump", many maps still show it as this. Signal Hill is well known for the Noon Gun, this is operated by the South African Navy and South African Astronomical Observatory. Since 1806 the Noon Gun has been a historical symbol of time keeping in Cape Town.

These guns, which are 18 pounder smooth bore muzzle loaders, were originally used to announce the arrival of an important ship and to allow ships at sea or in port to check the accuracy of their marine chronometers. However, after the introduction of the galvanic telegraph it became possible to trigger a gun remotely.

Therefore, since 1864 the Noon Gun has been accurately fired from the master clock of the oldest timekeeper in the country, the South African Astronomical Observatory. These guns, which are the oldest guns in daily use in the world, are fired everyday at 12 noon sharp, except on Sundays and Public Holidays.