The name may be simple, but it is wholly appropriate — the edge of the miniwall attracts a multitude of fish life and is a hive of activity, easy to visualize as a bustling city with its inhabitants going about their respective roles. A short way east of the pin is a large formation of Pillar Coral — a fantastic hard coral that grows in vertical columns and is unique among hard corals in feeding during daylight hours. A close look reveals tiny polyps with extended tentacles picking up morsels from the water. At 8–10 feet tall, this ancient formation grows exceptionally slowly and should never be touched.

Large schools of French and Bluestriped Grunts inhabit the little grooves east of the Pillars, making for beautiful photos as they move gently back and forth with the water. Eagle-eyed and patient divers can search the shallow hardpan areas for Lettuce Sea Slugs — just an inch or two long, their frilly backs store algal chloroplasts that allow them to photosynthesize energy from the sun. Sometimes called Solar-Powered Slugs, these tiny creatures are one of the ocean's more extraordinary animals.