I also tend to hike until dark when solo hiking. While some like to hit the trail early in the morning, I will delay my departure so that I'm not sitting around camp with my thumb up my butt. If I know that I will be arriving early, I'll bring a book (paper) to read to pass the time.
Unlike some people, I've never been bored in my entire life - I don't know what boredom is, frankly. So if there is down time, I'm probably going to find some way to enjoy it by birdwatching, wildlife sighting, or even reading a book.
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