Signal Hill: listen to the noon canon

You can tell tourists and Capetonians apart very easily. Just wait for noon.

When you hear the boom, tourists will look around confused, wondering what that was.

Capetonians will look at their watch. And maybe set it.

Since 1806, every day at noon, a canon is fired from the – appropriately named – Signal Hill.

Rising over the neighborhoods of de Waterkant and Bo-Kaap, two canons are kept in service to signal noon.

Those two canons are the oldest ones in daily use in the world today.

They fire every day at 12 noon sharp, except Sundays and public holidays, and are operated and maintained by the South African Navy.

The question of longitude

Initially, the signal was meant for the ships in harbor, so that they could set their chronometers aboard to the correct local time, and help them navigate on their long journey around the Cape, or back home to Europe.

Knowing the precise time in one place and measuring the time difference to noon at the place where you are right now, was vital for any ship, so they could calculate the exact longitude they were on.

So vital that the British Parliament in its Longitude act, set a substantive reward for anyone who could construct a marine chronometer reliable enough that could withstand the constant movements of the ship.

So, untill today, one of these canons is fired at noon.

Initially, the guns were placed at the Cape Town castle, in the heart of the city, but the very loud boom of the cannons unnerved people nearby.

And on top, the sound of the gun proved to be too inaccurate for ships several kilometers away. The speed of sound simply is too slow.

So the guns were eventually moved from the city to the Lion Battery on Signal Hill where they are today.

That way, ships could set their time by watching for the visible puff of smoke from the gun fire rather than the sound. That’s why the canons are placed that high above Cape Town harbor.

Witness the ceremony

We went up Signal Hill to watch the little ceremony, and listen to the navy officer performing it for decades.

He told us about the canons, and the improvements that have been made over time.

In earlier centuries, the observatory in Cape Town would measure the exact timing of noon, and then fire a flare up in the sky. The officer on duty would have to see that flare, and run over to fire the canon.

However, due to clouds or fog, and depending on the length of the fuse, that system was rather unreliable, and the noon boom wasn’t always accurate.

Today’s system is electronic. The observatory sends over an electronic impulse a few microseconds ahead of time, so that the canon is fired on time.

Only if the first canon for some reason fails to fire, the officer quickly has to press a button and fire the second one, that is also always loaded with gunpowder.


This ceremony is one of Cape Town’s oldest living traditions.

The officer told us about a few incidents, like the rammer being left in the canon, flying into the city and killing a horse. But maybe that’s sailor’s yearn… he’s working for the Navy, after all.

For the record, only on 7 January 2005 both the main gun and backup gun failed to fire, due to a technical problem. It was the one and only time in 200 years that the noon gun had not fired as scheduled.

If you want to watch the ceremony, come up a bit earlier, by 11.30, as the little parking spot fills up quickly.

Watch out as the cars get scared by the boom, and the alarms start honking!

You’ll also have time to enjoy the view over the city, Table Mountain, and Green Point and the Stadium.

You can also follow the noon gun on it’s twitter account. Wherever you are, you’ll receive a bang at noon, Cape Town time.