The Duomo, a landmark cathedral in Milan, is an imposing Gothic church dating back to the 1300s. The magnificent cathedral took five centuries to build and its façade has been sited for its captivating beauty by famous writers such as Mark Twain. As one of the most famous buildings in all of Europe, the Duomo is the largest Gothic cathedral and the second largest Catholic cathedral in the world. Inside the Duomo are five wide naves divided by 40 pillars, a statue depicting Saint Bartholomew, among others, numerous paintings, and is even said to house one of the nails from Christ's crucifixion. Tourists can venture onto its massive roof, which is renowned for its ornate pinnacles and spires.