Dagobah

Dagobah is a planet-wide swamp under permanent fog: gnarled gnarltrees, black water, dragonsnakes and bogwings, with no cities, no technology and almost no visitors. What sensors read as interference is something else - the planet is saturated with the living Force, including a cave strong with the dark side where visions confront those who enter.

Yoda chose this oblivion for his exile after Order 66, hiding for over two decades as a mud-hut hermit. Here he trained Luke Skywalker in 3 ABY, lifting his X-wing from the swamp to prove that size matters not, and here he died in 4 ABY, becoming one with the Force after confirming the truth about Vader.