Not all lights go out after the sun goes down. In fact, in some places of the world, they switch on, illuminating the night with glowing orbs and neon sparkles. Some are manmade, like glow-in-the-dark murals that wake up after dark and walk-through attractions dedicated to neon and light sculptures. But many are the handiwork of Mother Nature. From bioluminescence that lights up bays and beaches to caves that flicker with thousands of glowworms, here are some of the world’s most extraordinary places that glow in the dark.