looking down into Pueblo Bonito. The enormous blocks of sandstone are all that remain of Threatening Rock (behind us) which collapsed January 22, 1941 after a year of heavy rains. The rockfall destroyed about 30 rooms that had been excavated in the 1920s. Pictures 13 and 39 shows something similar to what Threatening Rock was (altho they say is is onlyu about a quarter as large). chacoarchive.org/cr ... ito/