Out of the places you have listed, I've been to Kanazawa, Shirakawa-go, Kyoto, Osaka & Nagoya (just near the station area).
Kanazawa: I feel that Kanazawa stay 1 night should be enough. Get the 1day Loop bus (500yen i think) for you to visit the tourist attractions in the town.
Nagoya: I only spent 2hrs at Nagoya to stopover for lunch in-between my train journey from Takayama to Kyoto. Me and hubby love to eat King crabs whenever we can when we go Japan and (
nì©É¿@Dy©É{Æ@kC¹ÌVNÈJjðóA¼) is our fav brand. They have a branch at Nagoya that's within 7mins walking distance from the train station. You might want to give it a try. I love their crab porridge (kani-zushi or something like that I think) and crab croquette.
See pics of our crab meal on my travel blog:
Go Away, Sam...: Japan (Jul11) Day 7: Takayama to Kyoto via Nagoya
Kyoto: Go Kiyomizu-dera, Gion, Arashiyama (bamboo groves & scenic train), Fushimi Inari Shrine...wear comfy shoes. You'll need them
Also there's 1 entire floor selling ramen & another floor with restaurants at the top 2 level of Isetan at Kyoto train station. There's also some food stalls at its basement.
Osaka: If you have extra time in Osaka, you might want to give Nara a visit in the morning-afternoon. Also I like to visit Tokyu Hands (a dept store) whenever I go Japan. They have branches at Osaka too, 1 at Osaka station itself which is on 9-11floor of Daimaru I think. Go online to check from their website before you fly. If you like donuts, try Krispy Kreme donut (there's a outlet at the basement of "Lucua" dept store at Osaka station).
Have you considered going Takayama? Personally I prefer Takayama over Kanazawa. Easy to take the 50mins bus ride from Takayama train station to Shirakawa-go as well. And Takayama is just a 2hr direct train (Ltd Exp Wide View Hida) from Nagoya to Takayama.
If you are getting JR pass and travelling by trains, it's best that you do your train reservations once you arrive at Japan. Because it's a super peak period over there (cuz the Japanese will also be travelling around during this time of the year) so reserve your tix as soon as you can for the rest of your trip.
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my travel blog:
Go Away, Sam...