Yggdrasil

An actual tree, deep in jungle, gives life to entire jungle, is protected by the Circle of Eternia (dryad druid group). Coiling trunk, all sorts of life grows in it. The entire tree comes straight from the center of the planet, where 5 waterfalls all also pour into. The base splits into three main roots, which lead into Tartarus, Hell, and Hades, while the highest reaches of its branches stretch into Celestia.