Now back in the Great Bath
We could actually see bubbles rising to the surface as we got closer to the big pool. During the height of Roman civilization this area was covered by a huge vaulted ceiling. This bath was the largest constructed north of the Alps. Hot water at a temperature of 115 degrees Fahrenheit rises here at the rate of 240,000 gallons every day and has been doing this for thousands of years. No wonder ancient people saw this as something mysterious.