I know what you're thinking. No, I'm not going to Japan quite yet. I'm planning a four or five week trip a few years down the line. I need that time to earn enough money as well as vacation time. But I will be going.
One of my goals during this trip is to climb Mt. Fuji. At over 12,000 ft, it's a bit of a climb. However, it's not especially steep, and the process of well organized. There are a series of stations. Each station sell overpriced water, food, primitive sleeping arrangements, and various knickknacks. You can even buy bottled air, if you're having difficulty breathing at such high altitudes. While I'll avoid much of this, one thing I want to do is buy a walking stick with your nation's flag attached. At each station, they burn a mark in it, saying you made it there. At the top, they have a special one, including one only given if you are at the top for the sunrise. They even have a post office at the top, so you can have a postcard that is postmarked from the top of the mountain.
A second goal is to visit a series of Japanese gardens. I haven't planned a lot of this out, yet, but I'm a big fan of the five styles they employ, except for maybe the sand one. While on my road trip a few years back, we stopped at the Japanese gardens in Portland, OR. I really enjoyed it there, and hope to visit again.
A third goal is to visit some of the JAXA sites. JAXA is the Japanese Aerospace Exploration Agency, Japan's version of NASA. They have done quite well in unmanned missions, including giving us the most detailed map of the moon ever taken. There are JAXA sites on all of the major islands and on some of the small ones. Most offer some kind of tour. As someone who grew up new Cape Canaveral, FL, watching shuttle launches, I'm really looking forward to this.
Other than that, I have no other plans. I do wish to see some of the temples and shrines, all four major islands, some of the major cities, and the memorials to the victims of the atomic bombs we dropped on them during WWII. It's going to be a great trip.