There are Nativity scenes (pessebres in Catalan) for every preference: big, smalls, traditional, modern… We have them at home and then in every city or village, they put their own.
In Barcelona, for example, it is a tradition to have the Nativity scene in Plaça Sant Jaume in front of the city hall. In the last years, it has been a very controversial issue as each year the scene has a different approach. This year 2021, it is located in Carrer de Ferran and Carrer Jaume I, so not in Plaça Sant Jaume haha
It is also a tradition to have live Nativity scenes around Catalonia. One of the most famous is Pessebre de Corbera de Llobregat although this year, due to the pandemic has been cancelled, but if you click in the link you will be able to see more info and photos 🙂