Go niche

If you are inclined to choose a hotel on the strength of its pool, why not take things a little further and build an entire holiday around one.

As with everything, the leisure industry has been pushing the envelope on what constitutes a cool pool.

Want to swim on top of a skyscraper? No problem.

Fancy taking a dip in a glass-bottomed pool cantilevered out over a city? No bother.

Your own private lap pool? How quaint.

To really take things up a notch, how about Crocosaurus Cove (crocosauruscove.com) in Darwin, Australia?

There you can work on your breast stroke and become bosom buddies with a deadly reptile at the same time, with crocodiles just inches away from you behind a glass screen.

Enter the Cage of Death if you dare and have the pool attendant instigate a feeding frenzy while you are tucked safely in a glass box.

If sharks are more your thing, it has to be the Tank at the Golden Nugget (goldennugget.com) hotel in, where else, Las Vegas. There guests shoot down a glass tube through a shark aquarium – for kicks.

For thrills of another kind, check out Nemo33 (nemo33.com) in Brussels, the world’s deepest diving pool.

Whether you are into scuba or free – good old-fashioned holding your breath – diving, it is the place to go.

Nemo33 is 34.5m deep and contains millions of litres of un-chlorinated, filtered spring water maintained at 30 degrees.

It even has underwater caves and lots of film crews use it to shoot underwater scenes.

All that’s missing is a wreck.