I was coming home. As I pulled in my garage, hit the brake to stop and put in park. The vehicle started winding up to a point where my foot on the brake didn't matter. It accelerated forward, going through the wall of my garage, through my backyard, thru a chain guard, and into the corner of the museum wall next door. I was finally able to stop it completely by shutting the vehicle off. Despite the speed and impact to the front of my vehicle, the airbags never deployed.