Hinterkaifeck was a small farmstead near the Bavarian towns of Ingolstadt and Schrobenhausen. It was about 70 kilometres (43 mi) north of Munich. On the evening of 31 March 1922, the six people who lived in the farm were killed. The murders remain unsolved.
The six victims were parents Andreas Gruber (63) and Cäzilia (72); their widowed daughter Viktoria Gabriel (35); Viktoria's children, Cäzilia (7) and Josef (2); and the maid, Maria Baumgartner (44).
Hinterkaifeck was never an official place name. The name was used for the remote farmstead of the hamlet of Kaifeck, located nearly 1 kilometre (0.62 mi) north of the main part of Kaifeck and hidden in the woods (the prefix Hinter, part of many German place names, means behind), part of the town of Wangen, which was incorporated into Waidhofen in 1971.