Sometimes the most interesting things are not found above ground, but below – as children playing on a mountainside in the 1930s discovered. Forgotten since the 1700s, the “Castle Mountain Caves” or "Schlossberghöhlen", were re-discovered after a young boy fell down a hole into one of the caverns.

Underneath the Hohenburg castle ruins, (a former French stronghold, torched in the 17th century), is the Schlossberghöhlen. This unique man-made cave system consists of eight caverns and over three miles of passageways stretching through a dozen floors. Historians believe these underground passages were originally created as escape routes for the castle residents above, before being mined as quarries for raw materials used in glass and iron production.

Underground, multicolored layers of yellow and rust-colored sand, rich with quartz and mineral deposits also provide important historical markers into how the caves were formed, and even periods of flooding through striations in the ceiling. During World War II, the caves also took on a new role, housing up to 5,000 people at a time as a shelter during bombings.

Paths are well-marked, and although a hardhat comes with the admission ticket, the caverns are open and spacious, making it a fun excursion for the whole family. Temperatures, as expected, are cool, so dressing in layers is recommended. After touring the caves, finish the day by exploring the castle ruins for an impressive view of Homburg.

TIP: To guarantee an English-speaking tour – it is imperative to call ahead for reservations and a time slot. Additionally, due to stairs leading to the caves, and the sandy floor of the caves themselves, strollers are not advisable.

How to get there Drive and park at the top of Castle Mountain next to the fortress’s ruins and follow the staircase path behind the Schlossberg Hotel to the cave entrance. Look for the directional signs: Schlossberghöhlen. Alternatively, you can walk up the mountain from a path starting at St. Michael Kirche, however, be advised it is a very steep walk.

Schlossberghöhlen Homburg Schlossberg-Höhen-Straße 66424 Homburg Phone +49 (0)6841 / 20 64 Hours: 10 a.m.–4 p.m., Tickets: 5 euros for adults, 3 euros for children

All photos - © Kristi Adams