I wouldn't go on first date hike... for reasons of safety to vanity (who wants to get sweaty on a first date?)...
BUT... I absolutely would go on a hike with a guy I felt comfortable with. In fact, I think that taking it down a real level (hiking is pretty real... no heels, fancy hair or make-up) is an excellent way to test the tenor of your budding relationship1
I live close to severa well populated hiking trails in my town. Or we could walk/hike through some architecturally interesting neighborhoods. Either works!
Nah, I won't...too many cute looking psychos around lol! Just kidding, but seriously I won't. Come on, it's a first date. Somewhere central and within civilisation i.e. within the city or the town will be more like it for me. When we get to know each other better, a hike would be great.