Denver was two cities - Auraria (correction from Aurora thanks to @negativenull) and Denver. One was built to align with the river, the other with compass points and then they grew big enough to smush into each other and neither was willing to concede to the other.
Also Denver’s namesake, a Kansas politician, never even visited. It was a failed attempt to lure him here.
OMG thank you - brain fart on my part!