Torre Nueva

A series of centennial towers are spread along the whole coast on the South of Spain, some of which are still standing. One of the best preserved towers is in La Linea de la Concepcion, the Spanish town that borders the British Overseas Territory of Gibraltar.

The sea-facing structure has one room some 13 feet (four meters) above ground. This room was the place were soldiers kept a constant eye to the south, where Africa is just about 10 miles (15 kilometers) away. The guards who manned the tower sent smoke signals to warn the locals of Berber pirate attacks. 

Torre Nueva doesn't have any sign explaining its origins. It was once possible to go up the ladder and enter in the guards' room, but the lower ladders are now gone since it seems people were using the room to organize social gatherings around alcohol and drugs. 

The road going to the tower is interesting as well, as it belongs to a failed urbanization project that was never built. Many constructions stopped development in the 2009 financial crisis.