Closing the ski season on a high note, Colorado-based resort company Aspen Skiing Co. announced yesterday that they’re acquiring Intrawest Resorts for $1.5B.

Those who haven’t heard of Intrawest have likely heard of their well known-mountains, including Winter Park, Steamboat, Stratton, and Snowshoe.

The purchase is a big move to help Aspen (which previously only owned 4 mountains) catch up with its biggest rival, Vail Resorts…

Which has been consolidating like crazy

The world’s largest resort operator has been on a buying spree itself lately, dropping $1.1B to buy most of the Whistler ski area in Canada, and $50m to buy Stowe in Vermont.

Why does one resort need so many mountains? To sell “Epic Passes,” of course.

Priced at $809, the awesomely-named pass gives skiers access to any of Vail’s 11 mountains. So more mountains equals more epicness — which equals more money. And with 650k passes sold last season, the strategy appears to be working.

Now with Aspen’s Intrawest purchase, multi-resort passes are simply table stakes. Other resorts have no choice but to buy a place at that table, or operate as a loss, getting people in the door while making the real money on bison chili and jacuzzi bubbles.

Not that we’d complain.