The Clérigos Tower is the undisputed most famous landmark in Porto. It was opened in 1763 as the tallest bell tower in Portugal, designed by Italian architect Nicolau Nasoni, and considered a National Monument since 1910. The tower is 75 feet tall Meters above ground, it houses a spherical clock house above, and is distinguished by its magnificent and majestic Baroque decoration, and includes an internal staircase (240 steps) that gives access to the summit, which offers one of the most beautiful panoramic views in all of Porto.