Ooooh, interesting one there Matt, hadn't thought of that.
Won't be an issue in Australia as our highest mountain, Mount Kosciuszko, is only 2228m high, and I've been there in December 1975, which was the last time you could drive a vehicle within 200m of the summit, then walk the rest of the way to the cairn at the top.
As a footnote:- we rode our motorcycles to the top on that December 1975 trip, then walked to the summit. While at the summit we saw snow that had turned rather icy on the eastern slopes, we donned our waterproofs, then proceeded to slide down on our backs and backsides a few times, a wonderful time was had by all and sundry. Couldn't do that these days, too easy to injure yourself; or something like that.