The frame is sturdy, with a geometry similar to a mountain bike, but with a more upright seating position than a mountain bike - less strain on the arms and better visibility. For longer journeys, often adapted to fit a variety of accessories such as mudguards and racks.
The wheels are robust, suitable for a wide range of terrain and for fitting wide tyres. Ideal if you like to ride on tarmac as well as on forest tracks. The 28" wheel size is suitable for longer trips.
Front shock-absorbing fork - for comfort, better grip on different terrains, to get around obstacles, and for safer downhill descents.
The chainring is partly hidden under the chain guard, or placed on the frame to protect it from scratches. Usually left fairly open for easy access when replacements are needed.
Plastic mudguards are often added to keep the overall weight of the bike to a minimum, to accommodate the optional luggage rack.
Saddle narrower, stiffer (compared to city bikes) for a sportier seating position.
Both dynamos for comfort and separate battery lights to maintain a lighter construction.