 While serving as an administrator for Hangzhou , the poet Su Shi ( <unk> – 1101 ) had a large pedestrian causeway built across the West Lake , which still bears his name : <unk> ( <unk> ) . In 1221 , the Taoist traveler Qiu <unk> visited Genghis Khan in <unk> , describing various Chinese bridges encountered on the way there through the <unk> Shan Mountains , east of <unk> . The historian Joseph <unk> quotes him as saying : 
