My wife, never learned to bicycle as a kid (grew up on an island without roads). Although I taught her to ride she was terrified every time and hasn't been on a bicycle for 25 years. Today she saw someone on a tricycle and said she thought maybe she could handle that and might be a good way to get some exercise. There are some hills around so some gears might be helpful (mostly, nothing over 3% for where she would ride). Any suggestions? I don't mind spending some money and want something reliable. I'm a good bike mechanic, but I don't want to be continually tweaking junk. I think she would be more likely to want an upright one than a recumbent. Suggestions?

I forgot to mention: She is 4'10".