Gravel
The majority of these routes is off-pavement. Tire choice tends to wide and treaded for volume and grip. Some events dip into XC/MTB terrain, so be ready. Most events send their routes out into remote areas, spreading any support crew across a large area so carry anything you need to solve any problems which might arise; tubes, chains, spare brake parts.
Groad
Mostly paved-road routes with off-road segments tough enough to want some volume in the tires and some durability in the bike. Drop-bar is the way to go, so these are going to be done on road bikes which can take generous road tires or gravel bikes on lighter, faster slick and file-tread kicks.
MTB
Some gravel events are gnarly enough that suspension, big tires, dropper posts and even the heads-up position of flat bars are the way to go. Others require an MTB setup, often for good reason.
Road
Fast, far... Depending on elevation gain, aero is generally going to be the emphasis here. Road tires, the efficiency of deep wheels, and a comfortable riding position.
Tour
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