I guess my old hardtail GT with a susp.fork could qualify as a gravel bike (with susp fork). It's ridden lots of MD-PA-W.VA rail trails, as well as some rocky, rooty singletrack. Still going strong. I'm an "older" rider, haven't yet grasped the diff. between a "gravel" bike and a rigid mtn bike with a drop bar. To me, a flat bar "gravel" bike would be the same as a rigid mtn.bike. Seems many gravel bikes are steel framed, as are some older rigid mtn.bikes. Guess wheel size could be a diff between the two, as many older mtn.bikes were 26" wheels.