Bull Run is a shark-focused reef off Bimini where scattered coral heads, sand lanes and algae patches create a broad maze that divers visit for close passes from resident Caribbean reef sharks. Most dives weave between the larger heads and low caverns, with swim-throughs and sandy openings breaking up the route instead of one single wall or wreck line. Planning stays important even though it is not especially deep: the site is boat-only, overhead-style coral sections reward careful buoyancy, and divers should expect regular shark traffic throughout the dive.