Any advice on things to do in Mishima Shizuoka?
 

I'm going to be down in Mishima City in Shizuoka Prefecture for a few days.

Does anyone on this board have recommendations on what to see or do?

A quick google revealed a recommendation to visit "Hanna Onsen" but I wasn't able to locate it. Plan to search for it later.

In fact, any recommendation on a good onsen or even sento near Mishima Station would be welcome.

Sorry these web sites are all Japanese-only:

店舗のご案内 | 店舗数日本一の風呂屋｜極楽湯
Public bath type onsen. Closest from the Mishima station.

http://www.yado-sagashi.com/hp/kinsyoukan/room.html
Basically a hotel (onsen-ryokan) but bathing only is also available.

日帰り温泉の湯郷グループ｜湯郷三島
Public bath type facility.

http://www.manyo.co.jp/numazu/
A bit far from Mishima station but internet etc. is available.

Thank you. The Gokurakyu Onsen near Mishima Station looks the most appealing: 三島店｜店舗のご案内｜店舗数日本一の風呂屋｜極楽湯