Grottoes filled with precious murals and sculptures are concentrated along the ancient Silk Road in Gansu. The best known are the Mogao Caves, a "treasure house of oriental art", with 492 caves with murals and statues on the cliff faces. There are 45,000 sq m of murals and over 2,100 colorful statues, all of high artistry. In the south, grotto art is represented in Sichuan by the Leshan Giant Buddha, carved into a cliff face. Seventy-one meters high and 28 meters wide, it is the largest sitting Buddha in stone, showing the carving skill of ancient craftsmen.