Snežnik Castle (Slovene: Grad Snežnik, German: Schloß Schneeberg) is a 13th-century castle located in the southwest part of the Lož Valley near the settlement of Kozarišče in the municipality of Loška Dolina, Slovenia. Its name is coincidentally identical to a univerbation based on the Slovene word sneg 'snow', but is actually a Slovenized form of the name of the noble house of Schneberg, whose possession it initially was. The Schnebergs were followed by the houses of Lamberg, Eggenberg, , and Schönburg-Waldenburg.
The date of the castle's construction is unclear; its existence is first implied in 1269, by way of mention of its owner Meinhard von Schneberg (Slovene: Majnhard Snežniški, Latin: Meynardus de Sneperch). The castle itself was first mentioned in 1461, as the manor of Sneberk; at the time it was a possession of the Patriarchate of Aquileia, with the Schnebergs as their ministeriales. The family fractured the estate through multiple heirs; by the late 14th century the castle had several co-owners. In 1393, a quarter-share of it and several neighboring farms was purchased by William II von Lamberg, a relative of the Schnebergs; his descendants increased their share through the 15th century until they owned the entire estate, giving the castle its more-or-less current renaissance appearance as well.
By marriages, the castle passed to the Scheyer family, followed by the Prancks and, in the first third of the 17th century, the barons Rambschissl, who sold it to the Imperial governor of Carniola, prince Eggenberg. Along with Snežnik, the prince bought the lordship of Lož, moving its administrative center from the uncomfortable, hilltop Lož Castle to the more amiable and better-accessible manor at Snežnik. In 1669, Janez Žiga Eggenberg sold the Loš-Snežnik lordship to prince Janez Vajkard Auersperg, the count of Gottschee (Kočevje).