A few weeks ago I almost tripped over a fairly massive wild boar, dusk at the Hoge Veluwe. Super impressive up close (and the most dangerous animal in Europe right now). Fortunately I have very good brakes :)
It was over so fast that I didn't have time to get scared. There are quite a few of them in that area (~50) and I know it well so I'm somewhat prepared but normally you see them coming from some distance away, this one (a pretty beefy male) just sauntered out from between a bunch of trees very close to the bike trail.