The capital on the Aare is BERN, a city in Switzerland. It is the fourth most populous city in the country and is the de facto capital of the canton of BERN. The city is situated on the Swiss plateau and is crossed by the Aare River. It is home to many historical sites, including the Zytglogge clock tower, the Federal Palace, and the Old Town. BERN is also known for its medieval architecture and is a UNESCO World Heritage Site.