What games have what you'd call really good worldbuilding, and what in particular do you like about them?

https://en.wikipedia.org/wiki/Worldbuilding

Worldbuilding is the process of constructing an imaginary world or setting, sometimes associated with a fictional universe. Developing the world with coherent qualities such as a history, geography, culture and ecology is a key task for many science fiction or fantasy writers. Worldbuilding often involves the creation of geography, a backstory, flora, fauna, inhabitants, technology, and often if writing speculative fiction, different peoples. This may include social customs as well as invented languages (often called conlangs) for the world.