Colorado & Southern RailwayRocky Mountain Railroad Club Excursion - Denver to Lyon - October 1951 Engine 647 - October 1951 Engine 647 - October 1951 Engine 647 - October 1951 Engine 647 - October 1951 Engine 647 - October 1951 Engine 647 - October 1951 Engine 647 - October 1951 Engine 647 - October 1951 Engine 647 - October 1951 Engine 647 - October 1951 Engine 647 - October 1951