The King Hussein Mosque, also known as the Al Husseini Mosque, is located in the heart of downtown Amman. The site was originally home to Philadelphia's old cathedral. A mosque was built there in the seventh century, and rebuilt in 1924 in the Ottoman style. It is one of Amman's more impressive mosques, and an important gathering spot in Wasit Al Balad. Even if you don't go in, it's a good photo op, and a great place to get a feel for Amman.