This article is from the Mountain Biking FAQ, by Vincent Cheng.
International Mountain Bicycling Association has set up a list of rules
that mountain bikers should follow. Please respect these rules as they
are what many mountain bikers live by.
IMBA Rules of the Trail
1. Ride on open trails only. Respect trail and road closures (ask
if not sure), avoid possible trespass on private land, obtain
permits and authorizations as may be required. Federal and
State wilderness areas are closed to cycling.
2. Leave no trace. Be sensitive to the dirt beneath you. Even on
open trails, you should not ride under conditions where you
will leave evidence of your passing, such as on certain soils
shortly after a rain. Observe the different types of soils and
trail construction; practice low-impact cycling. This also
means staying on the trail and not creating any new ones. Be
sure to pack out at least as much as you pack in.
3. Control your bicycle! Inattention for even a second can cause
problems. Obey all speed laws.
4. Always yield the trail. Make known your approach well in
advance. A friendly greeting (or a bell) is considerate and
works well; don't startle others. Show your respect when
passing others by slowing to a walk or even stopping.
Anticipate that other trail users may be around corners or in
blind spots.
5. Never spook animals. All animals are startled by an unannounced
approach, a sudden movement, or a loud noise. This can be
dangerous for you, for others, and for the animals. Give
animals extra room and time to adjust to you. In passing, use
special care and follow the directions of the horseback riders
(ask if uncertain). Running cattle and disturbing wild animals
is a serious offense. Leave gates as you found them, or as
marked.
6. Plan ahead. Know your equipment, your ability, and the area in
which you are riding - and prepare accordingly. Be
self-sufficient at all times. Wear a helmet, keep your machine
in good condition, and carry necessary supplies for changes in
weather or other conditions. A well-executed trip is a
satisfaction to you and not a burden or offense to others.
 
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