Welcome to The Illinois Institute of Diving, IID. Your Full Service SCUBA & Snorkeling Dive Center!  Everything from Instruction, Gear, Sales to Service! Located in Glen Ellyn, the Western suburbs of Chicago. Classes start every week with flexible schedules. Every class from basic, advanced, shipwreck, tri-mix to instructor. We include for free a lifetime warranty on instruction. Sales include Scubapro, Mares, Sherwood, TUSA, Aeris, Dacor, Poseidon, Viking, Atlan, Pinnacle to name a few.