Arenenberg Castle with Chapel and Park, Château in Salenstein, Switzerland

Arenenberg is a château above Lake Constance in Salenstein, built in the early 16th century by Constance mayor Sebastian Geissberg. Its pale yellow walls carry a steep green-tiled roof with two chimneys, a stone balustrade along the roofline, and a lower wing to the left. A lawn with a circular pool lies in front; inside, the rooms keep their original Empire furnishings.

Sebastian Geissberg, mayor of Constance, built the château at the start of the 16th century on the site of a farm called Narrenberg. In 1817 Hortense de Beauharnais, former Queen of Holland, bought it for 30,000 guilders and had it rebuilt by Johann Baptist Wehrle. Her son Louis Napoléon, the future Napoleon III, spent his youth here and planned his failed 1836 Strasbourg coup. Empress Eugénie repurchased it in 1855 and gave it to the canton of Thurgau in 1906.

The name Narrenberg, "fools' mountain", was gradually replaced by Arenenberg, perhaps after the Arnhalde slope below the castle. Hortense de Beauharnais kept a Parisian-style salon here, receiving guests such as Alexandre Dumas and Chateaubriand. The museum keeps much of the original Empire furniture, and the small neo-Gothic chapel stands before the entrance facing the lake.

The château stands above a lawn with a circular pool, facing Lake Constance opposite the island of Reichenau. The furnished ground floor and first floor are shown as a museum circuit, with the neo-Gothic chapel just before the entrance on the lake side. The park was largely restored for Napoleon III's 200th birthday in 2008.

The château's rooms keep their original Empire furniture, but Empress Eugénie removed valuable pieces before donating the estate to Thurgau in 1906, so several rooms had to be refurnished. The chapel by the entrance, facing the lake, is Neo-Gothic.