There is no mistaking how the hammerhead shark got its name: the head is flattened and extends outwards into the shape of a hammer, known as a cephalofoil. They appear so otherworldly since the head seems completely out of place on a fish with such a streamlined body.

However strange they may look, the benefits of having a head in the shape of a hammer cannot be denied. Scientists believe the wide-set eyes give the shark a better optical range than other sharks and the flatter, wider head means that the specialised sensory organs which detect changes in the surrounding water are spread over a greater area and thus have heightened sensitivity. Both these attributes are thought to maximise the shark's ability to seek out prey, resulting in an advantage over its competitors.

Hammerheads are found throughout tropical and temperate waters near the shoreline and also out in blue water. While the great hammerhead tends to be more of a lone ranger, scalloped hammerheads migrate polwards in the summer to find cooler waters in huge schools and if you are in the right place at the right time it can be breathtaking.

So where can you go diving with hammerhead sharks? Well for the big schools the trick is to head to oceanic islands which are far offshore surrounded by deep water.

Our top picks are as follows:

  1. Komodo, Indonesia - nutrient rich water surrounding these islands attracts big pelagics including big schools of hammerheads!
  2. Galapagos Islands - scalloped hammerheads are abundant around Darwin Island and Wolf Island.
  3. Cocos Islands, Costa Rica - far offshore these islands are famous for large schools of hammerheads, sometimes over 100! We haven't been here yet but we can still help you.
  4. Layang Layang, Malaysia - the atoll is set in 2,000m of water and 300km off Borneo, you are almost guaranteed schools in their hundreds at the right time of year. We haven't been here yet but we can still help you.

I saw my first hammerhead last year in Belize which was extremely exciting but to go diving with a huge school of hammerheads is right at the top of my list.

Have you been diving with hammerhead sharks? Tell us your story in the comments!