The Lower East Side Tenement Museum is a five-storey building that showcases the immigration experiences of internationals and was home to about 7,000 people until 1935. The museum features heartwrenching exhibits, such as "Under One Roof", which follows the lives of three families who used to live in this very building, one of which even survived the Holocaust. Do note that the museum can only be visited on a guided tour that can be booked online.