3. Solar Furnace (Odeillo, France)
This cool building was built by Felix Tombre, a French engineer. The shape of this building isn’t just a coincidence. It’s actually designed this way, so that all the mirrored surfaces can reflect light from the sun, and concentrate it in one spot, the size of a cooking pot. That spot is on the building in front of it, and it reaches crazy temperatures of 3500 degrees Celsius. This building is often used by various companies, agencies and scientist for their experiments. If you’re wondering how helpful can it be, well, let’s just say NASA uses it, so it must be really impressive.