The trekking bike is the northern European equivalent of the British tourer, only with a flat handlebar and a more casual, less mile-eating focus. It's a tarmac-and-gentle-tracks hybrid, factory-fitted with the accessories you'll want for weekday commuting or weekend wandering. A hybrid is fitted with 700c wheels (the same diameter as fitted to racing bikes) but with wider tyres and rims (on average 35mm). These tyres are generally multi condition, in that they have a smooth centre line for efficiency on tarmac, but have knobbly outer tread, to give good traction if the bike is ridden on a non tarmac surface. They are fitted with the same gear systems as mountain bikes, with between 21 and 27 gears, flat handlebars and cantilever or linear pull brakes. Better models feature "fully equipped", ie they come factory fitted with mudguards, and panniers, and some offer suspension seat pillars and adjustable rise stems.