In the early 20th century, when railroads were booming, train companies sent out photographer William Henry Jackson to snap photos. The idea was to use Jackson's shots of blue streams and craggy cliffs to woo the middle class into participating in Western tourism by train. Indeed, Jackson's softly colored images--part photography, part lithography--peppered railroad stations, ticket offices, hotel lobbies, schools, and even private homes for a time. Yet today, those images bear little resemblance to advertising as we know it. Instead, they offer insight into the railroad culture of the 1900s, as well as the photography technologies of the era. Tue-Sun, through May 31, 11 a.m.-3 p.m. Byers-Evans House Gallery, 1310 Bannock St. 303-620-4933; Free