I was in Lillehammer, Norway, a few years back. It's probably most famous for being the site of the Winter Olympics in 1994, but it also possesses a very big and very fine open-air museum, Maihaugen, which contains a huge selection of vernacular Norwegian buildings. The collection was started by a dentist, Anders Sandvig, in the late nineteenth century. When it outgrew his garden, the city of Lillehammer gifted him with a permanent site. Most are traditional rural structures, but there are several short streets of urban buildings, and a scattering of twentieth century houses.
The setting is lovely; the attention to detail comprehensive. Everything is neatly labelled; everything is explained. The traditional turf roofs provided good insulation and their weight stabilised the wooden buildings. Most guttering and most tools were wooden because worked metal was expensive, and so on, and so forth. It's a great museum, an idyllic simulacrum of a vanished way of life. It is, in short, an object lesson in worldbuilding. A ready-made stage set for a fantasy trilogy.
But like all museums, you wouldn't mistake it for the real thing. When you step inside one of the farmhouses, there's no sense of trespassing on someone's home, someone's life. Everything is an exemplar: authentic, but without the individuality of human context. Worldbuilding is, let's face it, isn't that difficult. A few basic principles, a few rules, consistency, coherence . . . Making it come alive, that's the hard part. That's where the work really begins.