The attraction of the depths.
There is always something fascinating and mysterious about exploring the deeper dive sites.
Sometimes it's a wreck that attracts you beyond 18 meters / 60 feet, or along a drop-off, it may be a huge gorgonian or a giant sponge.
Either way, to confidently dive to depths of up to 40 meters / 130 feet,
you should follow the PADI Deep Diver Specialty.