Gravel shoes sit right between road and mountain bike shoes, giving you a balance of pedaling efficiency and off-bike walkability. They use a 2-bolt cleat system (like MTB shoes) so the cleat sits recessed in the sole, but they have a stiffer midsole than most mountain bike shoes for better power transfer on long gravel rides.
The tread is moderate—grippy enough for hike-a-bike sections or cafe stops, but not as aggressive as a dedicated trail shoe. This makes them ideal for gravel racing, bikepacking, and any ride where you're splitting time between pavement, dirt roads, and occasional off-bike time.
If your rides are mostly pure road, stick with road shoes for maximum efficiency. If you're constantly off the bike on technical terrain, MTB shoes offer better protection. But if your riding blends both worlds, gravel shoes are the versatile sweet spot.