Tokyo to Kiso Valley to Gero

Hi there,
I'm going to Japan in September. I'm wondering if the following day plan would work:
- Travel from Tokyo to Kiso Valley (Arrive at 10am)
- Spend 5-6 hours in Kiso Valley (is this enough time?)
- Travel to Gero (45 min away?)

I need to arrive at Gero before 5:30 as we have booked our ryokan stay there.
Any suggestions?

Thanks in advance.

in kiso valley it really depends what you are doing: if you make the walks between the waterfalls, it can take probably a day. if you just go through the villages, 6 hours will be more than enough.... but i recommend to get also opinion from other users, cause i didnt had time to explore everything there.

There are two ways to go to Gero from Nakatsugawa.
One is by bus service and the other is by JR.
In case of bus, you can take a bus leaving Nakatsugawa station bus stop at 15:29. It arrives at Gero at 17:20. Bus fare is 2,400 yen.
JR train is also available departing at 15:06 at Nakatsugawa station and arriving at 17:24 at Gero station via Tajimi and Mino Ota using limitted expresses. In this case, the fare is 4,100 yen.
In any case, you don't have much time to stay in Kiso valley.
Here's a website for bus service:

http://www.navitime.co.jp/bustransit/search?orvArea=00&orvStationName=...