Bern, Switzerland's fourth largest city and the de facto capital of Switzerland, has a UNESCO listed old town tucked into the River Aare. A lot of the old core is from the 15th century and is laced with several kilometers of arcades covering shops and eateries. The Swiss Parliament and diplomats meet in the Neo-Renaissance Bundeshaus (Federal Palace). In addition to being a center for government, Bern also claims Albert Einstein and the modern artist Paul Klee as native sons.