I recently learnt of an easement in British law called the Right to Light, better known as Ancient Lights.
It basically allows a home owner, who has had a window that has received natural light for at least 20 years, to forbid an adjacent property owner from constructing anything that would block this natural light to the window.
I read about an unfortunate situation where a person bought a house in England in the 70's, and didn't notice that one of the windows had been blocked from the neighbouring property (as seen below), in an effort to bypass this easement law. The neighbour was successful, and later was able to construct a building on their land that continued to block this window.