the brand brings its influence to the great outdoors this fall.

Most people celebrate their 40th birthday with a lot of champagne, but for Calvin Klein, it's different.

Sure, there will be champagne, but that's not all - the legendary fashion brand hypes its four decades of existence with a giant outdoor sculpture, a new modernist building, and a celeb-studded walk through the garden on New York's Highline - a still-secret park floating slightly above the city.

On September 7, Calvin Klein unveils its gift to New York: An original building by John Pawson, the renowned architect who also made CK's store on Madison Avenue.  The semi-permanent structure will be gorgeous, giant, and fitted with another sculpture - this one, a giant light wall by artist James Turrell called The Space Division.

The building will be placed on New York's Highline, leading the fashion pack - and presumably celebs like Kate Bosworth and Eva Mendes, both faces of Calvin Klein - to an all night party.

And you thought rainbow frosting was the best birthday treat...