20160404. East elevation of Toronto’s once Consumers Gas Co. Purifying House No. 2 and now the Canadian Opera Company’s Opera Theatre.

20160404. East elevation of Toronto's once Consumers Gas Co. PurArchitects Strictland and Symens, 1888, Renaissance Revival.

The building was designed in the style of an early Christian basilica with a clerestory roof. It may have been built as a self-supporting structure and simply placed on top of the building so that any explosion would raise it without destroying the walls (from the COC’s website).

20160402. The Three Sisters of Pittsburgh.

20160402. The Three Sisters of Pittsburgh.These three self-anchored suspension bridges span the Allegheny River in downtown Pittsburgh. From front to back they are the Roberto Clemente Bridge, the Andy Warhol Bridge and the Rachel Carson Bridge.

Built from 1924 to 1928, they are the only trio of nearly identical bridges, as well as the first self-anchored suspension spans, built in the United States.