Up until bank deregulation in the mid 1980's, Colorado was a unit banking state, and a very restrictive one at that. Banks coudn't do any business, even back office or IT (computer) functions, in more than one building. This finally resulted in banks having very large buildings like the Wells Fargo one shown here to work in. When Wells Fargo took over First Interstate Bank in 1996, FI only had three banks in Colorado -- Denver, Englewood and Boulder, each previously run separately. Prior to the takeover, Wells only had branches in California. The Englewood FI bank was a massive building for the size of the city, and the First Interstate in Denver had two skyscrapers downtown that stood diagonally opposite each other on a city block, connected by walkways at the corners of various floors to make into "one building". Wells-Fargo must have taken this location over later than 2000, and it would have grown to this size much before then. Don't ask me how I know this!

Where the First National Bank once stood, a Brutalist-tinged Wells Fargo now hulks:

For reference (check the matching notches in the background mountain): Main Street, Montrose, 1939.

Some beautiful gold leaf on all those windows which banks and their tenants typically employed.

There are a bunch of similarities here but if they are the same there have certainly been some serious alterations done. A matching building from the same architect perhaps? ¯\_(ツ)_/¯

[Wrong intersection! - Dave]