The station first signed on in 1923 as KFEL, owned by Gene O'Fallon and broadcasting from the Albany Hotel. It is Denver's second-oldest radio station. After several frequency moves, it eventually settled on its current location of 950 AM. O'Fallon sold the station to Standard Examiner Publishing of Ogden, Utah in 1954, and the new owners changed the call sign to KIMN. For most of the next three decades, KIMN was Denver's highly rated Top 40 outlet. It was KIMN that presented the Beatles at the Red Rocks Amphitheatre in August 1964. The station was inducted into the Colorado Music Hall of Fame for its contribution to the Colorado music scene in the 1950s and 1960s. By the mid-1980s, KIMN evolved from Top 40 to oldies.
KYGO Country
At Noon on April 26, 1988, after airing a 12-hour retrospective of KIMN's history, the station flipped to Country music and adopted the KYGOcall letters. The programming was separate from co-owned 98.5 KYGO-FM. While the FM station concentrated on current and recent country hits, KYGO 950 used a deeper library and more personality. It was also a CBS Radio NewsNetwork affiliate. KYGO 950 continued for six years playing country music before its owner, Jefferson-Pilot Communications decided on a new direction for the station.
Switch to Sports
On October 12, 1994, the station changed its call sign to KKFN, and the station began adding sports talk programs to its schedule. On March 6, 1995, the station completed its shift to becoming the Denver market's first ever sports radio station as "AM 950 The Fan.". The simulcast only lasted six months.
Cruisin' Oldies
On September 2, 2008, the AM station became KRWZ with an oldies format, using the moniker "Cruisin' Oldies 950." On December 8, 2014, Entercom announced it would purchase Lincoln Financial's entire 15-station lineup in a $106.5 million deal. Until the transfer was complete, Entercom operated the outlets under a local marketing agreement. On December 22, 2014, Entercom announced that it would retain KRWZ and its oldies format. The FCC approved the deal on June 26, 2015.
Return to Sports
However, on December 17, 2015, Entercom announced it would sell KRWZ to KSE Radio Ventures, owned by Stan Kroenke. He added the station to his three recentlyacquired FM properties in the Denver market. KSE also announced that KRWZ would flip to a new format when the sale closes, as Entercom moved the Oldies format to KEZW on December 27. On the same day, KRWZ began stunting with mostly adult standards music, as well as redirecting listeners to KEZW. Upon the change of ownership, KRWZ adopted the call letters KKSE. KSE announced that the station will return to sports talk and become "Altitude Sports 950". The new format's programming will include the Rich Eisen Show, along with a schedule of live and local programming. The station was to serve as the radio flagship for the Colorado Avalanche, the Denver Nuggets and the Colorado Rapids, as well as the Colorado Mammoth. The sale to KSE closed on March 14, 2016, and the station flipped to a simulcast of KWOF that day at Noon. "Altitude Sports 950" officially launched at 7 a.m. on April 8th. KKSE entered a crowded sports talk field in the Denver market, with competitors including KDSP, KDCO and former sister stations KKFN and KEPN. On September 17, 2018, KKSE moved its local programming to 92.5 FM, with 950 AM becoming mostly a pass-through for Fox Sports Radio programming. The move was made due to its new FM sister's stronger range. The AM station must conform its nighttime signal to protect XEQ-AM in Mexico City, while the FM station provides at least grade B coverage to almost all of north-central Colorado.