Robert Lyon started in the automobile business in Saskatoon back in the 1950s. By the mid-1960s, Bob Lyon was running Trader Bob's Used Cars, which had become a big success. He eventually sold that business and moved on to Estevan, Saskatchewan, where he formed and operated Lyon Chevy-Olds, which rapidly became a very successful General Motors dealership.

While in Saskatchewan, he took skiing holidays wherever he could. During visits to the U.S., Europe, and Alberta, the idea of developing and operating his own family ski area was slowly forming. By 1970, he had decided to abandon the security of his well-established automobile dealership and develop a new ski area.

He chose Calgary as his new base. After looking at several potential areas, he found 240 acres of land near Bragg Creek known as Lusk Lake. Lyon purchased the land, and in subsequent years was able to expand the property up to 1,280 acres. Lyon started tree clearing on the east face of the mountain in 1971. One year later, he attempted to procure a development loan from the Alberta Opportunities Commission to purchase and install a T-bar and day lodge. Bob Lyon wanted to open the area for the 1972–73 ski season. This did not work out because the Commission felt that Lyon needed a snowmaking system before they would give him the loan.

Instead of giving up, he began formulating plans to include the development and sale of country residential properties near the base area. In 1974 he purchased another quarter section of land, and by 1977 roads and utilities were built for the development.

While Lyon had slowly been completing the ski hill, he was still short of cash to finish it. With an economic downturn, people were not as willing to buy lots at Lyon Mountain. Lyon had purchased a Müller double chairlift from the defunct Telemark Valley ski area in Vernon in 1980 and had re-engineered the lift to eventually be able to run in a double-double style. However, he was still short around $2 million, which was needed to make the ski area operational. Thus, in 1984 he applied again to the Alberta Opportunities Commission for a loan, to which they agreed.

In 1985, Lyon Mountain opened with two T-bars, one double chairlift, and Alberta's first quad chairlift, all installed by GMD Müller. The resort boasted a modern snowmaking system with snow guns and grooming machines. As Lyon quoted on opening day: "I'm the happiest guy in town. I admit it has taken a long time to complete the Lyon Mountain ski and residential project, but wasn't it well worth waiting for?"

Lyon's entire goal with the ski resort was to keep it affordable. As he put it: "I'm a family man and I was critical of hills that don't cater to the family. I wanted something where a family could come and not get gouged."

Unfortunately, 1985 was the end of Bob Lyon's ownership of his mountain. In July of 1986, Lyon Mountain was placed into receivership. Bob Lyon had reportedly missed two payments to the Alberta Opportunities Commission, which cost $76,000 each. Despite his best plans, the ski hill lost money during the first year of operation due to an unusually warm winter which made it impossible to blow snow.

The ski area was operated by a court-appointed receiver for two years until a new group of local Bragg Creek investors purchased the assets and renamed the ski hill to Wintergreen in 1988. According to the investors, the name Wintergreen reflected the fresh, clean country atmosphere of the facility.

Wintergreen didn't last long in the hands of the four investors, as in 1989 the ski hill was sold to Alberta ski giant Charlie Locke. Locke also owned Lake Louise and Fortress, and his ski hill empire slowly grew to include Kicking Horse, Fernie, Kimberley, Mont-Sainte-Anne, and Stoneham. His new company was called Resorts of the Canadian Rockies.

In 1996, a serious accident occurred on the lower mountain Deer Run T-bar that injured eight people. The lift was installed in 1985 and served beginner terrain. According to the mountain, one of the cables jumped off a pulley, sending it tumbling down the hill onto skiers. Thankfully no skiers were killed or seriously injured. In the aftermath of the incident, the T-bar was permanently closed and removed later that year.

In 2001, Charlie Locke found his empire unraveling. Locke had built RCR on the model of Intrawest, minus the vast funding that Intrawest had behind it. After an economic downturn, Charlie Locke found himself in financial trouble, unwilling — or unable — to pay back an $8 million bill required by a cash call. Charlie Locke's initial plan was to sell the golf courses and non-essential ski resorts such as Fortress, Wintergreen, and Kicking Horse, while focusing on restructuring the company. However, investor Murray Edwards stepped in and purchased a majority stake in RCR. As Charlie Locke explained: "Murray had $800 million and I didn't."

Unfortunately, the early 2000s brought some rough conditions, resulting in warm ski seasons across the board. Edwards had started cutting costs across all RCR resorts, which included shuttering mid-mountain lodges at Lake Louise, reducing grooming schedules, and other measures. Looking to cut costs further, RCR made the decision to close Wintergreen after the 2002–03 ski season. The golf course was kept operational, but the ski hill was completely shuttered. Most of the lifts were removed and the snowmaking and grooming equipment was distributed to other RCR resorts. RCR also closed Fortress in 2004.

In 2015, RCR proposed developing the former ski hill into condominiums, with the hill to be home to a mountain development featuring several stages of condo development. The plan was ultimately rejected by the county based on water proposals RCR had not adequately addressed.

Since then, Wintergreen Ski Hill has been abandoned, with one chairlift remaining on the mountain. Most of the base facilities are still used for the golf clubhouse. Despite sizable interest in the reopening of the ski hill, it will most likely never be reopened to the public.