Castellar de la Frontera is situated in the Parque Natural Los Alcornocales, about 10 km north of Algeciras. It is divided into two parts: the Old Town (also named Castillo de Castellar or Villa Fortaleza) and the New Town.

The old town is built on a hill 248m above sea level and is marked by a big stronghold. In ancient history this strategic position made it easy to oversee and guard the surrounding area. To get there you take the A369 from San Roque (exit 116). After about 7 kilometers you have an exit to the left, with a sign Castillo the Castellar. From this point you drive 3 kilometers uphill, on a steep road. When you are almost at the end of the road, and can see the stronghold in front of you, there’s a viewpoint (mirador) on your right side. From this point you have a nice view over the surrounding area; the Parque Natural Los Alcornocales.

In ancient times various civilizations inhabited the place; Iberians, Romans, Visigoths and Muslims. The stronghold originally dates back to the 10th century and was built on top on an old roman settlement. The stronghold as we can still see it nowadays is mostly built in the 13th and 14th century, during the Muslim era. Some parts are changed and added later, during the Christian era.

You enter the Villa Fortaleza through a gate in the main wall. Near the main entrance gate you find the Alcázar. Since its original construction this building has been changed a lot but there are still some original features left. Close to the Alcázar you find the Iglesia del Divino Salvador, built in the 17th century on top of an old mosque. Until the 19th century this church also served as a cemetery. From the castle you have a nice view over the Embalse de Guadarranque (water reservoir).

Since the depopulation in 1971, when most people from the old town moved to the new town, the old town is a peaceful and quiet place. Only recently it becomes more popular to live here again, especially among foreigners. Like most old Spanish cities there are a lot of pretty narrow streets, white buildings and plants and flowers to look at.

Although most people go to Castellar de la Frontera to visit the old town, the new town is also worth a visit. The new town is situated a few kilometers southeast of the old town, downhill and only got populated since 40 years ago. With its broad streets, terraced houses and tidy gardens with lots of grass and flowers it looks more like an American suburb than a real Spanish town. It has a lot of roundabouts, all very well kept with in the middle either a fountain or a statue. In the centre you find the main Plaza with a small park, some bars/restaurants and a very modern looking church.