The two nicknames that you listed for Rochester, New York ("City Built by Hands” and “Snapshot City"), never really caught on. But the town does have an official nickname with an interesting history. After the Erie Canal was completed in 1825, Rochester, with water power from the falls of the Genesee River, became one of the largest grainmilling centers in the world and called itself “Flour City.” After that industry declined, Rochester became better known for its parks and horticulture businesses. Not wanting to throw away a perfectly good nickname, city fathers simply changed the spelling to the current “Flower City.”