Driving from Kumamoto to Mt. Aso

We are planning to drive from Kumamoto to Nakadate crater in Mt Ado in early September then staying overnight st an onsen in Kurokawa. How is the drive from Kumamoto to Nakadate crater? And how long will that take? According to the map, it is about 60km but it takes 2 hours?

Thanks!

How is the drive from Kumamoto to Nakadate crater?

Easy, especially if you have a GPS navigation system. All along major roads. The roads have even two lanes in each direction for a considerable section of it.

And how long will that take? According to the map, it is about 60km but it takes 2 hours?

Yes, that sounds like a good estimate. Probably under two hours. It depends on where in Kumamoto you depart from and on the traffic situation.

Thanks Uji! We will be picking up the rental car at Kumamoto JR then head to Mt Aso.

What about the drive from Mt Aso to Kurokawa? Is it mainly small roads?

Google map shows the drive between Kumamoto JR station to Aso ropeway station to be about 75 min at a distance of not more than 32 km.
http://goo.gl/maps/v1VGl

Another 10-12 min will bring you up to Nakadake Crater, but note that depending on volcanic activity this access road may not be opened all the time. If it is opened you have to pay a toll.
http://goo.gl/maps/qV71e

The drive from Aso ropeway station to Kurokawa Onsen is just slightly over an hour.
http://goo.gl/maps/k3op2

Thank you very much!

The worst part of the drive will be from JR Kumamoto to Ozu but traffic can still be bad all the way as far as Tateno gorge, the entrance to the caldera. Most of the traffic turns left here and follows the northern caldera floor toward Oita and Beppu. The south side toward Takamori generally has less traffic. You can go on the south route 325 to get to the mountain entrance. You turn left at a Family Mart convenience store off of 325 to go up the volcano onto route 111 . I often pick up stuff there and take it to an abandoned picnic shelter about half way up. There's an empty parking lot on the right with some steps going uphill to the shelter. You can't see it from the road or the lot.

A better route can be picked up at Ozu as you head east on 57 called the "Milk Road." If you pick it up in northern Kumamoto City, it will follow the old sankin-kotai road that the daimyo used to travel to Tokyo during the Edo Period. The trees that are planted alongside this road all had an economic value, such as the mulberrys. You will also pass Miyamoto Musashi's grave (the 2-sword technique fighter). The road eventually gets you on the north side of the caldera with several stopping points to overlook the caldera floor and the 5 peaks of the volcano. You can then drop down into the caldera and check out the Aso Shrine in Aso before going up the north side to Nakadake.

You have a couple of choices on heading north to Kurokawa but I usually follow the Yamanami Highway for a short ways through the grasslands before turning west to the onsen.

Thanks for the detailed instructions Anaguma!