This mountain city in Bulgaria is known as the Machu Picchu of Europe but is less crowded and easier to get to, while still full of ancient mysteries.

The medieval settlement included an inner city-citadel on a high rocky plateau, an outer city and unfortified suburbs.

Rome for a breathtaking look at the Italian capital - Want to see a destination from the best vantage? Up the altitude. Here are the top spots from which to appreciate the Eternal City ...