The original Moscow Kremlin was built in the 14th century. It was reconstructed by Ivan, who in the 1480s invited architects from Renaissance Italy, such as Petrus Antonius Solarius, who designed the new Kremlin wall and its towers, and Marco Ruffo who designed the new palace for the prince. The Kremlin walls as they now appear are those designed by Solarius, completed in 1495. The Kremlin's Great Bell Tower was built in 1505–08 and augmented to its present height in 1600.