Every park or preserve district can have slightly different rules and regulations, therefore it's a good idea to check the information signboard at the preserve entrance, or the website before you leave home. Here are some general guideline for trail safety and courtesy.
Bicyclists yield to hikers, who yield to equestrians. As a hiker, assume you will be the one to yield, for safety's sake.
When meeting an equestrian on a small trail (i.e. not a fire road), make verbal contact with the rider from as far away as is practical. Stop, and step aside to the outside of the trail, if there is one. Wait for the horse to pass. Don't touch the horse (I know, it seems a friendly gesture)!
When approaching anyone on the trail, make the other person aware of you. When you overtake someone from behind, try to make a noise to let them know you're there before you are on top of them. I've found a discrete cough to be okay. I've been on the other side of this more than once with joggers, who come up behind you very quickly and may startle you.
Stay on the trail. Switchbacks erode hillsides, and make for long
hours of trail maintenance. Unofficial trails make it very confusing to
discern the proper course. To keep your impact minimal, refrain from gathering
any plants, rocks, or other items you may encounter on the trail (garbage excepted).
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