The Monastery of St. Simeon in Aswan, Egypt is a cool fortress-like spot that was first dedicated to a local saint who ditched his wedding for the monk life. It was rebuilt in the 10th century and has some ancient graffiti from Muslim pilgrims. You can reach it by private boat and a desert walk or by camel if you're feeling fancy. The place used to house up to 1000 monks, but got a bit wrecked by Saladin's troops in 1173. Check out the frescoes in the basilica and the old mastaba beds in the cells. Don't forget your water bottle!