Walking through the bustling Cape Town waterfront, you will see many old and new buildings, many of which have a maritime history. Perhaps one of the most important of these buildings is a tiny unsuspecting tower with a large ball on top of it. 

This tower, aptly called the Time Ball Tower, is an 1894 time device similar to the one in the Greenwich Observatory in the United Kingdom, which was used to give a visual signal of the time to ships in the bay, as this was much more accurate than an auditory signal like those of the noon gun, simply because sound travels much slower than light. This was a vital task, as a ship's clock (or chronometer) was needed for navigation, and any drifts could blow a ship off course or worse.  

The tower was initially built on the former Royal Observatory, Cape of Good Hope, but an 1860s expansion of the harbor obscured the old tower, which created the need for a new one. Initially this was a wooden tower, which was later replaced by the current model in 1894, which remained in use for another 40 years. 

Since then the need for time balls dwindled, and so did their maintenance. The tower was used for a while as a signal repeater for the area, until it was declared a monument and restored in 1997. Since then the time ball has been operational again, and used on occasion.