A30 is an indoor deep-water training pool near Saint Petersburg that is built around a controlled depth progression rather than natural scenery. The facility is useful for scuba, freediving, and introductory water work because it gives beginners shallow platforms and advanced divers deeper training levels in the same place. Instead of reef life, the appeal is the structure: multiple platforms, a steady year-round environment, and a full training venue with support spaces, gear, and instruction.