At the San Alfonso del Mar resort in Algarrobo, Chile, there's a swimming pool like no other. Over 1 km long (yes, correct, 1,000 m), covering 8 hectares (roughly the size of 13 football pitches) and containing water enough to fill 6000 normal pools, this is one pool where you shouldn't have to worry about colliding with anyone else when swimming lengths! However, maybe you should watch out for boats as they're also sharing the incredible pristine surface of this awesome beauty.