Originally Posted by
Cyclesafe
Also, the image conjured by "gravel roads" varies. If what is meant is "degraded-chip-seal", then 37-622 is fine. If what is meant is a "four-wheel-track-with-gravel-dumped-in-the-low-spots-for-drainage", then you'd want something considerably wider.
For the former, I like the Schwalbe Marathon Cross in 36mm. For the latter, I prefer the IRC Mythos in 42mm. I've put hundreds of rough miles on the Mythos and thousands on the Marathon Cross with 0 flats and excellent handling.