Speaking of the 1920s, just the other day EphemeralNY posted this etching by Martin Lewis, titled “Fifth Avenue Bridge.” It dates to 1928, and shows the flapper set crossing what looks like a wooden bridge, along or over 5th Avenue. The bridge was likely put up to deal with construction, and one commenter on the site noted, "It’s very possible the bridge was built during construction of the new Independent subway which crosses 5th Ave at 53rd St." (The line was conceived in 1920 to deal with severe overcrowding on the subways.)