Angyal-forrási Cave, Protected cave in Tata, Hungary.

Angyal-forrási Cave is a protected cave in Tata composed of conglomerate and sandstone rather than typical karst rock. The walls are covered in calcite deposits left by mineral-rich water flowing through the formation.

The cave was first documented in 1976 as the Tatai tavasbarlang and appeared as Angyal-forrási-barlang in 1980. It was declared a nationally significant cave in 1976 and a strictly protected cave in 1982. Archaeological finds, including a nummulite in the gravel, were recovered from the cave floor.

The cave's name comes from the Angyal-forrás (Angel Spring) whose funnel opens in Tata's Angolkert, in the Tóváros district of the Duna–Ipoly National Park. Hungarian literature lists it as Angyalforrás-barlang (Bertalan 1976), Tatai-tavasbarlang, Pokol-forrás, Angyal-forrás barlangja (Eszterhás 1992) and Angyal-forrás Cave (1989); the form Angyal-forrási-barlang was first used in 1980.

Access to the cave requires special permission from the Duna-Ipoly National Park Directorate as a protective measure. Visitors should arrange authorization in advance and follow all site regulations.

The cave's floor layers hold tiny pebbles polished to a mirror shine, mostly quartz, including transparent rock crystal, carnelian, jasper and chalcedony. A sandy layer is so rich in magnetite that about one cubic metre of fill contains 10 kilograms of magnetic iron ore, as György Vajna reported in 1977.