The construction of what came to be known as Prague Castle began near the end of the 9th century, expanding a fortified settlement that had existed on the site since the year 800. The first masonry under Prague Castle dates from the year 885 at the latest. The other prominent Prague fort, the Přemyslid fort Vyšehrad, was founded in the 10th century, some 70 years later than Prague Castle. Prague Castle is dominated by the cathedral, which began construction in 1344, but wasn't completed until the 20th century.