Tom's Cave is a nice little cave dive on Lonsdale Wall. The entrance on the wall is at around 30 m (98 ft), then you proceed through the cave and exit at about 22 m (72 ft). It's an easy swim through for advanced divers. There is plenty to see in the area where you exit Tom's Cave.
Over the years we've been provided with many GPS marks for Toms Cave. The GPS marks we know of in circulation for Toms Cave are:
Dive Type: Wall Dive
Imported from The Scuba Doctor