You may know that this W.W. Boyington-designed Gothic limestone Water Tower and its Pumping Station were among the only buildings in the Great Chicago Fire's path left standing. For this reason, the Water Tower is now a beloved symbol of the city's resilience; in 1969, it was also the first building to receive American Water Landmark status. What you might not know is that the Water Tower was already a civic icon before the 1871 fire, when it stood in proud testament to Chicago's burgeoning commitment to public health. An engraved plaque inside the Water Tower commemorates a 2-mile aqueduct dug 60 feet under the lake bed, conceived by city engineer Ellis Chesbrough as a way to bypass the putrid river water and access the cleaner stuff farther out. Crews working round the clock finished the tunnel in three years; its 1867 completion, says Carl Smith in his book "City Water, City Life," "was one of the most heroic engineering feats in this age of such achievements." 806 N. Michigan Ave.