30+ Rare Photos Of Extraordinary Events In History – Check Out #8! #36 Columns Of Hoover Dam Being Filled With Concrete, February 1934 (Looking Upstream From The Nevada Rim) Credit: rarehistoricalphotos Prev Next Pages: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19