The term CITY ON THE AAR can be solved by two crossword solutions: BERN (4 letters) and BERNE (5 letters). BERN is the capital of Switzerland and is located on the Aare River. BERNE is an alternative spelling of BERN. The city is known for its medieval architecture, including the Zytglogge clock tower, which dates back to the 13th century. BERN is also home to the Swiss Parliament and the Federal Palace of Switzerland.