Originally Posted by
TenGrainBread
I'd say a modern gravel bike is a lightweight bike with >40mm tires, sensible gearing for steep terrain, and a more upright geometry for long distance. Sure, C&V sports tourers might have had sensible gearing and more upright geometry, but the wide tire and lightweight categories kill the comparison.
In my mind the only C&V subset that is truly comparable are the old 650b x 42mm French or Japanese randonneur-style bikes, the high-end ones that are below 25 pounds.
I'd add rigid mountain bikes, the Bianchi Project series, and the Bridgestone XO bikes to this list. Maybe these bikes are more classic than vintage but they all work very effectively as gravel bikes.