Don't be alarmed, but the ground beneath your feet is fairly percolating with superheated water. Countless natural springs and wells lie just below the surface of Budapest. As long as 2,000 years ago, the Romans were channeling this water into public and private baths in Budapest, at the settlement of Aquincum (literally 'abundant water'). Centuries later, the occupying Turks built baths; others in Budapest were built around the turn of the century, as new springs were discovered. Heated deep within the earth's crust, the thermal water in the baths often contains mineral water with natural healing powers. Some visitors come to the baths as treatment for ailments of the joints and arthritis (thus the many elderly bathers). Bust most come for pure soggy, steamy, flotational relaxation. "Plaques of gratitude" grace one wall of the Lukács, donated by happily healed bathers whose ailments were eased in the waters here. The current bath complex opened in 1984 but actually dates back a few hundred years. There's also a swimming pool.