Šaumburk, Castle ruin in Rajnochovice, Czech Republic.

Šaumburk is a castle ruin on a hilltop in Rajnochovice, with stone remnants showing wall sections and foundations of the medieval fortification system. The remains spread across the summit, revealing how the structure was once laid out.

Bishop Bruno von Schauenburg of Olomouc built the castle after 1272 as his representative seat and named it after his ancestral home in Lower Saxony. By 1275 a burgrave, Mikuláš z Choryně, is recorded there; damaged after Bruno's death, it was repaired and working again by 1307. A burgrave's office still sat there in 1320–1325, but its size and costly upkeep led to its demise, and by the mid-14th century nearby Nový Šaumburk had replaced it.

The castle takes its name from Bruno von Schauenburg's ancestral seat in Lower Saxony, and the Czech form Šaumburk is a rendering of that German name. A green-marked hiking trail from the Podhradní Lhota railway stop passes the site on its way over Kelčský Javorník to Loukov station.

The ruins are accessible year-round via marked hiking trails from the town of Rajnochovice in the Zlín Region. Visitors should wear sturdy footwear, as the terrain is hilly and the paths can be uneven.

The castle's name comes from Bishop Bruno von Schauenburg's ancestral seat in Lower Saxony, not from any Czech word. The site is protected as a cultural monument since 1973. A green-marked hiking trail from the Podhradní Lhota railway stop passes the ruins on its way to Loukov station.