Make sure that the area selected allows horses and that the trail is within the animals' capability. Park rangers and forest service personnel are generally helpful but do not know horses. Twice we have been sent on trails by well meaning government employees that were dangerous for the animals. Pick camp sites that allow grazing and water with safety. On top of a cliff is a bad idea. Carry grain as a supplement if grazing is expected to be poor. We often make unscheduled stops where there is good cane or grass, just to recoup the horses. On a hot day a thousand pound horse drinks up to twelve gallons of water at a single stop. I would not plan a trip where there is not adequate water.
Emergencies do occur. We carry a horse first aid kit (bandages, antiseptic, and oil for colic) and can handle most simple problems ourselves. If in a new area, a name of a local vet and their emergency number is a good idea. Check with your own vet before leaving home and make sure you have conformed to all health requirements. Many states are quite strict concerning tests and inoculations.
Finally, the trek should be enjoyable for both the person and the horse. Well planned and within everyone's abilities, a horseback trek can be an experience like no other. People and horses make great teams.
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