Red Basilica

The cathedral-sized Red Basilica was originally a giant temple to the Egyptian gods Serapis, Isis and Harpocrates, built in the 2nd century AD. It's still an imposing-looking place, though rather scattered and battered-looking these days. Be careful as you make you way around as several sections of the basilica's high walls are severely damaged.

During its pagan pomp, this must have been an awe-inspiring place. In his Revelation, St John the Divine wrote that this was one of the seven churches of the Apocalypse, singling it out as the throne of the devil. Look for a hole in the podium in the centre, which allowed a priest to hide and appear to speak through the 10m-high cult statue. The building is so big that the Christians didn't convert it into a church but built a basilica inside it. The most intact section, the southern rotunda, was used for religious and cult rituals; once covered in marble panels, it is now just red brick.

Along with the glass-topped northern rotunda, the curious red flat-brick walls of the large, roofless structure are visible from midway down the roads to the acropolis and town centre. You can easily walk to the Red Basilica, or stop your taxi there on your way to/from the acropolis.