As much as I love Japan's major cities, I quite enjoy leaving them as well. Places like Tokyo, Osaka and Kyoto have played crucial roles in my family's life, but it has been equally important for the four of us to get out of town and back in touch with the natural world. Now that summer is in full swing, it's a good time to explore Japan's spectacularly great outdoors.

For many families, summer is all about the beach, but for ours, Japan's mountainous areas are where the fun is. We've enjoyed plenty of hiking and camping on Japan's Honshu mainland, but the family favorite activity remains the same every year: white water rafting. All over the archipelago, people are donning helmets and life jackets in preparation for a trip down one of the country's many tumultuous tributaries. Some boat tours cater to those who want to float leisurely down placid waters, but we're not going to talk about those. The kids and I always want action, so we head to wherever the rapids are.

There are top-rated rafting courses near most major Japanese cities. The water is clear and bracing, but after paddling for an hour or two on a balmy afternoon, a dip in the frigid waters of a mountain stream is one of the most pleasurable and exciting experiences that the kids and I enjoy each year.