It is unlikely you will hurt yourself unless the bike is fit wrong. If you have the bike bug consider taking a bicycle maintenance course. See if there is a club in your area. Check tourist authorities for suggested routes. Get a paper street map of the area and see what is worth riding around. Sometimes bike paths you did not know about are on such a map.
2000 Montague CX, I do not recommend it, but still ride it.
Strida 3, I recommend it for rides < 10mi wo steep hills.
2006 Rowbike 720 Sport, I recommend it as an exercise bike.
1996 Birdy, Recommend.
Wieleder CARiBIKE (folding), decent frame.