. . . here's a video clip about what's billed as 'the hardest 400-meter run in Europe': the Red Bull 400. Held on a ski slope during summer, The Adrenalist described it as follows:
From the starting line at the base of the jump to the finish at the top, the course covers 400 meters and includes 180 meters of vertical gain. That equals an average gradient of about 45% or an angle of ascent of about 24 degrees, a pretty typical slope found on standard staircases. Cover that slope with slippery grass and stretch it the length of four football fields and now you’re talking tough.
I don't think I'll be tackling that anytime soon . . . but if you'd like to try it next time, see the event's Web page for details. We'll eagerly await word of how you did!