T-Höhle

The T-Höhle is a water-bearing cave in the Toten Gebirge in Upper Austria. It lies in the Rettenbachtal valley at 545 metres above sea level, where the Rettenbachalm road meets the Grabenbach forest track. The cave sits just before the bridge on the right bank of the Rettenbach stream. Its most striking feature is the many well-preserved Megalodon shells embedded in the walls. The cave formed along a bedding plane, creating a narrow trench up to two metres deep where the underground stream flows. Above this trench is a horizontal chamber that gives the cave its distinctive T-shaped cross-section. The stream disappears into the block debris only a few metres from the modest entrance. Inside, the passage runs northwest at first, keeping the T-profile, before widening into larger chambers in the rear half. The tunnel ends at a siphon where the water is forced back up. Visitors enter through a small opening hidden among the blocks. They follow the trench downstream, noticing the Megalodon fossils set into the walls. The ceiling stays low for most of the way, then rises in the wider rear section. The cave stays cool and damp, with the sound of running water filling the passages. Outside, the surrounding forest and mountain slopes frame the quiet valley where the cave is found.