Conditions at the site were primitive, with scientists having to ride out to the excavation on mules and staying at caravansaries along the way. When the first skullcap was unearthed at the site in 1929, it was done by Pei, "working in a 40-meter crevasse in frigid weather with a hammer in one hand and a candle in the other." A second skullcap was discovered close to the first in 1930 and by 1932 nearly 100 workers were deployed at the site each day.