Abstract: A modular snorkel includes a breathing tube, a snorkel body, a connector tube matingly and sealingly connecting the tube and the body. The breathing tube is rotatable relative to the snorkel body and has a plurality of vertically spaced ribs to which a mask strap retainer may be releasably secured in vertically adjustable, rotatable relationship. A valve located at the upper end of the breathing tube includes a valve housing configured to permit the free flow of air and the exhaustion of water from the tube, while restricting the entry of water into the breathing tube, especially due to splashing. The valve housing also includes a depending deflector to direct water purged from the upper end of the breathing tube towards and out the valve. The connector tube sealingly connects the breathing tube with the snorkel body solely through a friction fit. The snorkel body may be vented at a lower end to facilitate the release of trapped water.