Claim: Chushul Chakzam is a structure built in 1430 by Thang Tong Gyalpo which literally means “iron bridge."
Evidence: It was built in 1430 by Thang Tong Gyalpo. The Chushul Chakzam (Tibetan: ཆུ་ཤུལ་ལྕགས་ཟམ), or simply Chakzam which literally means "iron bridge" in Standard Tibetan, was a suspension bridge that spanned the Yarlung Tsangpo river in modern-day Qüxü County near Lhasa, Tibet.