Venture away from the city’s beaten path to the Szemlő-hegyi and Pál-völgyi caves. Follow guides from the Hungarian Caving Association and get access to some parts of the caves that most tourists can’t enter.  Go 500 meters into the two caves, which feature an unusual up-welling of warm, mineral-rich water. Learn why the Szemlő-hegyi Cave is referred to as the underground flower garden of Budapest and see its unique rock formations. Explore the interactive exhibition and educational trail.  Continue to the Pál-völgyi Cave and marvel at Hungary's longest cave system, around 32 kilometers. Find stunning stalactite and stalagmite formations, and glittering calcite crystals.  Experience the famous Theater Hall, renowned as an echo chamber with impressive acoustics. Finish your tour with a peek at the quarry from one of the caves' many hidden exits.