Brass Anchor Scuba Center - Based in Frederick, with instruction, online newsletter, dive travel, and local dive information. Atlantic Edge Dive Center - A PADI 5-Star instructor development center providing scuba sales, services and training. Includes instructor profiles, store hours, and map to location in Gaithersburg. Chesapeake Scuba - Snorkeling and scuba classes from beginner to instructor; equipment sales and service; underwater video and photo; travel. Olney SCUBA Adventure Dive Club - Club information includes membership details, photo gallery pages, dive reports, message board and classified ad section. Columbia Scuba - Store hours, contact information and details on various levels of PADI certification courses. Aqua Ventures Online - Equipment, classes, dive travel trips, local dive trips, Maryland and Delaware wreck dives, air and nitrox fills, repairs, and rentals. SK Divers - PADI instruction and dive travel. Dive schedule, services and web specials. Blue Marble Divers - Located in Hagerstown. See course offerings, equipment, services, and photos. Aquanautics - Full-service PADI 5-Star dive center in Baltimore. Offers instruction, travel and an online newsletter.