Hohenschwangau Castle or Schloss Hohenschwangau (lit: High Swan County Palace) is a 19th-century palace in southern Germany. It was the childhood residence of King Ludwig II of Bavaria and was built by his father, King Maximilian II of Bavaria. It is located in the German village of Hohenschwangau near the town of Füssen, part of the county of Ostallgäu in southwestern Bavaria, Germany, very close to the border with Austria.

Hohenschwangau Castle was built on the remains of the fortress Schuangau, which was first mentioned in historical records dating from the 12th Century. A family of knights was responsible for the construction of the medieval fortress, and it served as the seat of the local government of Schwangau. In 1523, the schloss was described as having walls which were too thin to be useful for defensive purposes. After the demise of the knights in the 16th Century, the fortress changed hands several times. The decay of the fortress continued until it finally fell into ruins at the beginning of the 19th Century.

In April 1829, Crown Prince Maximilian (the later King Maximilian II of Bavaria) discovered the historic site during a walking tour and reacted enthusiastically to the beauty of the surrounding area. He acquired the ruins - then still known as Schwanstein - in 1832. In February 1833, the reconstruction of the Castle began, continuing until 1837, with additions up to 1855. The architect in charge, Domenico Quaglio, was responsible for the neogothic style of the exterior design. He died in 1837 and the task was continued by Joseph Daniel Ohlmüller (died 1839) and Georg Friedrich Ziebland. Queen Marie created an alpine garden with plants gathered from all over the alps.