In October, you can enjoy Koyo (autumn leaves) in Nyuto Onsenkyo. Great to hike upon the Mt. Komagatake, also nice to walk in the beech tree forest around Taenoyu too.
Koyo season starts depends on the weather and temperature.
This is Tazawako Tourism Association’s website which shows the progress of Koyo. Check 乳頭温泉郷, it shows by colors Green to Red.
By train & bus
Bullet train “Shinkansen Komachi(新幹線こまち)” get off JR Tazawako(田沢湖) station.《Tokyo – (2h50min) – Tazawako – (1h) – Akita》
From the station, take public bus “Nyuto Line(乳頭線)”- 45min – get off “taenoyu-mae(妙乃湯前)”
★Bus time table from JR Tazawako station
6：55 7：45 8：45 9:40 10：40 12：25 13：20 14：20 15：35 16：35 17：20
To Akita airport, there are some flights from…
Haneda airport (Tokyo), Itami airport (Osaka), Chubu centrair airport (Nagoya) and Shin-chitose airport (Hokkaido)
from Akita airport to Nyuto onsen, take bullet train and bus (as above) or take “Akita Airport liner” http://akita.airportliner.net/en/