Hallwilersee

Aesch is a municipality in the district of Hochdorf in the canton of Lucerne in Switzerland.

Boniswil is a municipality in the district of Lenzburg in the canton of Aargau in Switzerland.

Birrwil is a municipality in the district of Kulm in the canton of Aargau in Switzerland.

Hallwyl Castle (German: Schloss Hallwyl; IPA: [halˈviːl]) is one of the most important moated castles in Switzerland. It is located on two islands in the River Aabach, just north of the northern end of Lake Hallwil in the municipality of Seengen in the canton of Aargau. Since 1925, it has been open to the public, and since 1994 it has been owned by the canton of Aargau and is part of the museum of Aargau.

Mosen is a former municipality in the district of Hochdorf in the canton of Lucerne in Switzerland. On 1 January 2009 it became part of the municipality of Hitzkirch.

Brestenberg Castle (German: Schloss Brestenberg) is a castle and manor house near the municipality of Seengen in the canton of Aargau, Switzerland. It is open to the public and today houses a museum and a cafe.

Lake Hallwil (German: Hallwilersee) is a lake largely in the Canton of Aargau, Switzerland, located at 47°17′N 8°12′E. It is the largest lake in Aargau and lies mostly in the districts of Lenzburg and Kulm on the southern edge of the canton. The southern tip of the lake reaches into the canton of Lucerne.

Leutwil is a municipality in the district of Kulm in the canton of Aargau in Switzerland.