Nagoya is the fourth most populated city in Japan, after Tokyo, Yokohama and Osaka.
Nagoya is the core of the Chukyo metropolitan area which is more than 9 million inhabitants, which is the third largest metropolitan area after Greater Tokyo and Osaka-Kobe-Kyoyo.
Then, it is the only metropolitan area which has only one city above 1 million inhabitants, Nagoya.
Greater Tokyo includes Tokyo, Yokohama, Kawasaki and Saitama. Osaka-Kobe-Kyoto has Osaka, Kobe and Kyoto.
Nagoya is located almost middle of Tokyo and Osaka and has distinguished culture.
The local foods include chicken wings, kishimen noodle, miso nikomi udon noodle and hitsumabushi eel rice.
Although Nagoya is not a place full of tourist attractions as like Kyoto, it is a gateway for very important and famous destinations thanks to its function as railway hub.
1) Takayama city - known as Hida Takayama is the historical city on JR Takayama line.
2) Shirakawago - UNESCO. Unfortunately no train connection at all but you can take a bus from Nagoya.
3) Ise jingu shrine - The most sacred place in Japan. JR pass holder can reach it by JR Sangu line via JR Kansai main line and semi-private Ise railways. Please note that you have to pay a supplement on board when you pass the Ise railways.
4) Gero onsen(spa) - Definitely the most famous onsen spa in the region which can be reached by JR Takayama line.
5) Magome and Tsumago - These are the former station villages(staging posts) on the Nakasendo route, one of the five major route in Edo period connecting Edo(Tokyo) and Kyoto. The nearest station is Nakatsugawa and Nagiso on JR Chuo main line.
Therefore you can stay a couple nights in Nagoya which is plenty of hotels and travel to these destinations on daily excursion basis.