What Our Divers Say

I must say WOW! Being an experienced diver, I did not expect such a wonderful tour coming! I loved it. Thanks a lot. Me and my friends had a lot of fun, learned some new techniques and saw amazing places. Great job!

Kelly Joel
Kelly Joel

Summer is a joyful season, the one that is absolutely perfect for traveling, falling in love and of course for diving! Book the best tour and find the perfect diving spot with the help of professional instructors!

Caren Page
Caren PageStudent

No matter how far you have to travel to try it, diving is absolutely worth it! Thank you for making my vacation truly unforgettable. I enjoyed every moment of it, and I do appreciate your assistance with all the arrangements.

Monica Barton
Monica BartonModel
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Captain Mark “Sharky” Alexander started diving nearly 25 years ago as a Public Safety Diver for the Springfield/Sangamon County ESDA rescue squad in Illinois. Sharky is an active recreational, technical, and closed circuit rebreather instructor and expedition leader, arranging and coordinating exploration expeditions around the world.

Sharky’s Underwater Expeditions was founded in 2007, and focuses on advanced dive travel, deep wreck exploration, specialized technical training and closed circuit rebreather training. Sharky specializes in closed circuit rebreather training and mixed gas training, as well as functioning as a dive medical officer, and offering medical seminars on remote medical treatment and logistics. For more about Sharky, click here.

Sharky has participated or led expeditions to many historic deep wrecks, including the Graf Zepplin, Andrea Doria, U-869, SS Carolina, USS Monitor and Gertrude Tomkins-Silver’s missing P-51D Mustang.

Sharky has had the opportunity to do television work with Capt. Dan Crowell, former owner of the legendary east coast dive boat Seeker. Sharky participated in the Military Channel’s Quest for Sunken Warships series, working on the episodes “Torpedo Alley” and “Truk Lagoon.” Sharky has also participated in the History Channel’s Weird US Series, working on the episode “Weird Underworld.”

In 2010, Sharky was inducted into the Explorer’s Club, and in 2012 into the Royal Geographical Society, in Britain.

For the latest updates to the Expedition and Training Schedule, visit our live Expedition & Training Calendar!