Cádiz is a city of more than 100 watchtowers, but none stand as tall and as proud as the Tavira Tower. The tower is 45m above sea level and acted as the official watchtower of the city during the golden period in the 18th century, with its name coming from the first guard tasked with peering out from its walls (Don Antonio Tavira, for the record). A Camera Obscura is now found up top, allowing visitors the chance to ponder the modern development of this most historic city. The tower is open all through the year with the exception of those major Catholic holidays around Christmas, and tickets are just €6.