Diving into history
A shipwreck is sometimes a great object to have a look at while you're diving. It cannot only be an artificial reef stuffed with corals and sponges, but it can also be the home for different species of fish.
You can also imagine how the wrecks used to look like and therefore it's a great plunge back into history. You can often explore wrecks inside and outside and that's what's makes it so interesting. When wrecks are very good preserved you can still see things like an engine, railing, mast, funnels and sometimes even weapons like cannons and guns.