The Guinness Book of World Records holds a world record of its own; it’s the best-selling copyrighted book. Here we take a look at the records set by daring and fun-loving scuba divers.

>>Deepest Scuba Dive in Seawater

• Ahmed Gabr
• 1,090 feet, 4.5 inches
• Red Sea off Dahab, Egypt
• September 18, 2014

While the descent took only 15 minutes, Gabr’s ascent took 13 hours, 35 minutes. His preparation — training both physically and mentally — took four years.

>>Longest Open-Water Saltwater Scuba Dive

• Cem Karabay
• 142 hours, 42 minutes, 42 seconds
• Cyprus
• July 20, 2016

In breaking the previous record — his own — of 71 hours, Karabay helped pass the time by playing chess and soccer with his support team. In 2011, he set the record for the longest scuba dive in a controlled environment — a pool in Istanbul, Turkey — for more than 192 hours.

Related Reading: How Your Fitness Impacts Diving

>>Highest Altitude Scuba Dive

• Erno Tosoki
• 20,938 feet, 3.84 inches
• Ojos del Salado, Chile
• February 21, 2016

It took five years of training and two failed attempts before Tosoki achieved his record. Ojos del Salado also claims bragging rights for being the highest volcano on Earth.

>>Largest Underwater Wedding

• Ewa Staronska & Pawel Burkowski
• 303 diver guests
• Jaworzno, Poland
• August 27, 2011

Staronska and Burkowski took the destination-wedding and trash-the-dress concept to a whole new level — or should we say, depth. The ceremony lasted about 18 minutes, and the couple communicated using waterproof paper and hand signals. Even the priest was a diver.

>>Longest Underwater Human Chain on Scuba

• 240 divers
• Deerfield Beach, Florida, USA
• June 17, 2017

After spending the morning conducting an underwater cleanup at a local fishing pier, the divers added world-record holders to their resumes. This record is still pending because Guinness has not yet verified it. The current recognized record — 182 divers in Thailand — was set December 27, 2016.