Kyoto to Kurokawa Onsen in one morning

My husband and I are going to Japan for 11 days this September. We mainly want to see Tokyo, Kyoto and the surrounding areas. My dilemma is that I really really want to go to Kurokawa Onsen too.

We really aren't too interested in seeing the cities between, we would rather spend the time in the Tokyo/Kyoto areas. So ideally it would be leave Kyoto early in the the morning 5am and get to Aso station and take a bus to Kurokaw Onsen. We would stay for the afternoon and 1 night and the next day head back to Kyoto. We are trying to be budget conscious so a taxi isnt really an option. And we wont be able to get a japanese license for a rental car.

Is it feasible to do this? Or will we end up wasting time on the train? Do you guys know of other onsen towns with lush green forests and boulder outdoor baths? I looked at Kinosaki Onsen, and though the town is cool, the baths don't have the vibe I was hoping for. Advice would be great.

I'm going to say no. Buses are the only real option to get to Kurokawa if you cannot drive.

I have also heard due to the recent earthquakes in the Kumamoto region the Hohi line is substantially impacted which if the damage is considerable, this will mean that getting to Aso will take a lot longer than usual, if it is accessible at all.

Kurokawa is really out of the way of the main locations you are travelling to. And as above, buses are required to get there. Let alone all the damage to the local area that will take months to fix.

To add to the above info. The Hohi Line has suffered massive damage and an area just north of Tateno Station has had a landslip effecting both the rail line and road bridges.

Kinosaki might be a better option with the limited number of days you have available to you. Much closer and cheaper to get to from Kyoto.

I would never do such a daytrip, because I think Kurokawa can only be properly appreciated with an overnight stay. If you were to pass through Kyushu, then a daytime visit would be understandable, but as a side trip from Kyoto: I personally would never do it.

If you do it (as a day trip or overnight trip), don't travel via Aso Station. It is a huge detour. Instead, take the direct bus from Fukuoka. I don't think that the roads between Fukuoka and Kurokawa have been damaged, and even if they will be by future aftershocks or landslides, they are very likely going to be fixed by September.

I would recommend shinkansen from Kyoto to Kumamoto and bus to Kurokawa onsen.

Travel by shinkansen and bus via Kumamoto is slower, more expensive and less frequent than travel by shinkansen and bus via Fukuoka.

The only reason I see why you would want to to travel via Kumamoto instead of Fukuoka is because you want to visit Kumamoto along the way.