Árbær Open Air Museum is like stepping back in time to experience Reykjavík's past. With over 20 buildings, including a town square, village, and farm, visitors can get a feel for how people lived in the city. From craft days to vintage car displays, there's always something interesting happening at this unique museum. Plus, during the summer, you might even spot some friendly domestic animals roaming around. It's a fun and educational way to explore Icelandic history right in the heart of Reykjavík!