On the east coast of Egypt's Sinai Peninsula, a few miles north of the city of Dahab, is a diving and snorkeling site known as the Blue Hole. Every day, divers make the journey from Dahab by jeep ...

One of Dahab’s most famous sites, the Blue Hole is considered the world’s deadliest diving spot. But its infamous reputation has only boosted the impressive sinkhole’s appeal to brave divers ...

Blue holes are considered an "oasis" for marine life — but the Taam Ja' Blue Hole off the coast of Mexico remains largely mysterious.

The Blue Hole, a 330-foot marine sinkhole in the Red Sea near Dahab in Egypt, is thought to have claimed the lives of about 200 divers.

It's a popular subject. There are more attractive dive sites than the Blue Hole of Dahab, with more colorful corals, and more fish, shipwrecks, channels and caves.

Scientists have yet to reach the bottom of the Taam Ja' Blue Hole in Mexico's Chetumal Bay, which new measurements hint could be connected to a labyrinth of submarine caves and tunnels.

So we filmed in Dahab, Egypt, in the Blue Hole with Alessia, in the Bahamas at the Vertical Blue competition and in a cenote in Mexico. How did that filmmaking process work?

Dahab blue hole ullstein bild via Getty Images Expert divers are attracted to the thrill of the Dahab Blue Hole, known as one of the most treacherous underwater sinkholes in the world.

The Taam Ja' Blue Hole off Mexico's Yucatán Peninsula has been discovered to be "the deepest-known blue hole globally," according to new research.

Infamous site: Situated an hour's drive from Sharm El Sheikh, Dahab is home to the Blue Hole, known as the world's deadliest diving spot.