Trinity Church was completed in 1877. This building is considered to be one of the ten finest examples of architecture in the United States and is the only church on the list. The architect was Henry Hobson Richardson, thought to be one of the three greatest architects in the history of the country (Frank Lloyd Wright and Louis H. Sullivan are the other two).

Because the Back Bay neighborhood is all landfill, the old buildings were built on spruce wooden pilings driven through the fill and into a thick layer of blue clay. The Trinity Church is on 4,502 wooden pilings.