Interesting unusual places from Nagoya

Hello.
I'll be attending a short course in Nagoya for 3 weeks but I will have some time off to do touristy things. I have planned out most of my days but I still have one weekend free. Any recommendations apart from Inuyama, Takayama, Shirakawa, Kanazawa and Sakushima island (these are already in the plan). I have already been to Tokyo, Kyoto and Osaka before.

So I'd like to visit and experience places I have not already covered. Meaning no temples/shrines/edo villages/onsen/theme parks/gardens. I am considering either Hiroshima (is it too far for a weekend trip) or going to Tokyo again.

Any other ideas?

Why not try Izu?

Or if you qualify, use ANA's Experience Japan Fare and fly to Okinawa, Miyako, Ishigaki, Nagasaki, Kagoshima, Sapporo, Hakodate, Akita.... and many more. Don't feel cooped up - you have the whole country wide open to you and within a couple of hours travel or less.

Use Google translate.
https://retrip.jp/articles/52807/
http://mnky.jp/21258
https://www.pairs.lv/2993
http://tokaidate.seesaa.net/

I don't think Hiroshima is too far. Assuming you can leave Friday evening, you'd have all day Saturday and much of Sunday there.

Nara to me is an obvious choice, but if you're sick of temples and shrines maybe that's not for you.

How about the Seto inland sea area with a visit to the modern art on Naoshima
http://www.japan-guide.com/e/e5445.html
http://www.japan-guide.com/e/e5475.html

Or if you are still in the mood for castles there is Hikone
http://www.japan-guide.com/e/e7001.html
Or Bitchu Takahashi where you can hike to it.
http://www.japan-guide.com/e/e5775.html

Personally though I would either do the Seto sea or Hiroshima.

Thanks everyone for your ideas!
Will find out more info about some of the places mentioned.

Hachiman

Take the Nagaragawa railway up there to Gujo-Hachiman Station. You wont spot another foreign tourist. The the trip up on the railway beside a river is experience in itself.

What about Nagoya?

Head to MejiMura for a day.