Image: via travelpod
Have you ever swam out in the sea and not been able to see the bottom? All you can feel is the freezing cold water beneath your feet; all you see is dark blue water extending to infinity.
Imagine for one second descending into the blue, deeper and deeper with every kick and breath. The adrenaline kicks in and as the pressure builds, water compresses your chest. You’re scared, but there is something strangely inviting about the descent that makes it feel like you’re travelling to the center of the Earth. Looking ahead and all around you can see only a wall that drops for meters into the blackness below, and it is inviting, alluring. Welcome to the world of blue holes.
Effectively limestone sinkholes, or submarine caves, blue holes are given their name because of the contrasting deep blue of the hole and the lighter blue of the shallows around them. There are a number of blue holes across the globe but only a few are frequented by divers, each with its own unique biodiversity. Here we present five of the best in the world: