We were out playing in the snow on Christmas Eve on the border of Vancouver and Brush Prairie on 152nd Ave. We fed and watered the horses and put them in their stalls for the night. On Christmas morning I went out and fed the cats. On my walk to feed the horses I noticed that the sliding doors to the arena were sticking out. I could also see the inside of the barn, which was not typical. Then it hit me...I noticed beams sticking up and more debris as I pressed on. I ran for the barn and realized the only words that could come out of my mouth, "Oh...my...god!" I ran in and right back out as soon as I saw the heads of the four horses inside. Fortunately, the line of stalls on the left and right sides of the arena housed the major large pilars holding up the barn. As you can see from the before and after photos, the arena inverted straight from the top point down. You could see the layers of snow, then a sheet of ice, and topped with another layer of snow. The weight must have been too much for the roof to handle. We got all of the horse out safe but not necessarily sound. 2 of the 4 were quite disturbed, anxious and nervous on the walk over to another shelter. Sadly, 1 of our 3 large barn owls was badly injured in the crash. He was picked up and put into a warmer, more stable environment. Unfortunately, he did not survive.