Not so tall... 1058m is where I'm standing. It's something that can be done in a couple hours from start to finish.

For a comparison, Mt. Fuji (which is Japan's tallest) is 3,776m (give or take a meter) so where I am is less than a third. But the 1000m range is about average for the mountainous areas around my home. If I want to do some "serious" hiking and mountain climbing, the Yatsugatake volcanic chain is nearby too. They range between 2000 and 2800m.

As for how the locals react to the kilt? Meh. It varies. I swear, some days I could walk down the street naked and no one would notice. Other days I get the strangest looks (kilted or not). It's really hard to gauge. Japanese people (in general) tend to keep a very level head and serious face (when sober) so if something were wrong or awry, they may never let on until long after you've left.