Years ago while I was in college I was biking into school on the bike path and came through an S curve and nearly hit a couple of deer standing in the path. All I could hear was those hoofs trying to get traction on asphalt.
Fast forward 20 years to last weekend. I'm biking up a road and hit an S curve and... bear about the size of a German Shepard (only much much more stocky). I hit the brakes and stop about 25 yards from it. Luckily after a second or so (felt much longer) it noticed me and scampered off--meanwhile, given its size I was busy scanning the woods for momma. Must have been older than I thought as none was found.
Biking up the rest of the hills was much easier after that.
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I've only seen bear in years past once (similar story as above, hiking, came around a corner, and there he was, only less than 25 yards away), and three times this year. They have come out of the woodwork in NH it seems. I might have to give in and get bells for my shoes.