Believe me your horse will associate a trail ride with fun, EVEN if you are working him all day along the trai.
Yesterday I rode in Bryce Canyon. Narrow trails with Steep drop offs. I was constantly asking my horse to yeild off my leg and get away from the edge.
We had to cross blown down logs, streams, mud. We passed through tunnels, and narrow gaps.
We moved at walk, trot and canter. He had to be soft when I asked him to. I frequenty asked him to bend both verticle and laterially. I practice my one rein stop frequently during a trail ride. I want to know that my horse WILL do a One Rein Stop 100% of the time, no matter what excite him.
My horses have to learn not to rush obsticles, to be patient when we have to cross them. To listen and respond to the queues I give to get around trail obsticles. When I ride in the canyon country, I don't want a horse getting excited and jumping off a cliff with me. I ride my horse through places lots of folks get off and lead. But I've taught my horses, even my young ones, to behave.
Your horse will learn to neck rein as you ride down the trails. The horse is going to follow the trail, the slightest touch of the reins on his neck will
Guide him down the trail, this become a habit for him that he will remember in the arena.