310 120 541030
Located on the US Air Force Academy, this is a short monopole that has only Sprint. As of July 2023, it's still active, and it still provides service at least as far as New Life Dr, east of Voyager.
Speed test at close range, Galaxy S22, close range: 63.03/40.46 Mbps, 78 ms (results)
Photos taken July 1, 2023
On reddit, No-Seat-407 identified the Whelen WPS-2905, which is a speaker for mass audio.
About 400 feet to the west is Verizon, and across Interstate 25 is another active Sprint site.
Nearby permit, not sure whether it's related: registration 1253084, FCC