Route Fukuoka - Nagasaki - Aso - Kurokawa onsen - Miyazaki or Kagoshima - Tokyo

Hi there,

This looks like an amazing trip! Kyushu is absolutely the best part of Japan! The trains are amazing too.

Let's dig in right away and see how to make the most of your trip.

The 1st thing I am wondering is about by Shubuko, do you mean a temple stay? The most famous of which is Mount Koya. I found one near Aso although I've not been there myself, so I don't know if it is any good.

Looking at your itinerary, I've got a couple changes for your to consider.
3 Nights in Nagasaki is time very well spend. However spending 2N may be a little long. You can see the Aso crater and surrounding area in half a day, so you may become bored if you plan to spend more time in the area. There are great hiking routes, so you don't have to worry about getting bored if you love hiking.

Kurokawa onsen and Yufuin are different onsen spots. Kurokawa is absolutely lovely but can be hard to get to because it is only reachable by bus. Yufuin is also not to be missed either. Yufuin is very accessible and there's a special train (known as the Yufuin no Mori) which travels directly to the town.

Also I would recommend swapping staying at Miyazaki for Kagoshima or Yakushima. There's multiple ferrys from Kagoshima each day to Yakushima and this would be the chance to fit it in. From Kagoshima you can also make a day trip from Kagoshima to Kirishima, one of the more hidden places in Japan.

Lastly going from Fukuoka - Tokyo, generally a domestic flight does not have to be very expansive. However since ticket prices change a lot it would be hard to say it it is cheaper than the JR. A normal ticket by JR ¥ 21,520, wha you could do for instance is buy a 7 week JR Pass and use it the travel to Tokyo. The price of a 7 day JR Pass is ¥ 28,300 so basically you would get an additional 6 days of unlimited travel for ¥ 6,780.

Hope this helps!
Daniel