Mishima and its nearby area offer many activity sites to enjoy nature and culture of Japan (more info). Mount Fuji is open only in summer (not June).
Mishima Area: walking distances
Hakone Area: 50 min by Tokai Bus N65 (every hour, 1280 yen)
Numazu Area: 5 min by JR Tokaido Line (next station, 190 yen)
Izu Area: 30 min or more by Izu-Hakone Line and Tokai Bus
Official tourism site is here in multiple languages (JP/EN/KR/CN/TH).
Gembe River (7 min from the venue)
Rakuju-en park with animals and old villa (3 min)
Sano Art Museum of samurai sword
Mishima Skywalk bridge (20 min by bus)
Hakone mountain is an active volcano, where you can smell sufur with smoke (official tourism site). The lake is the result of an eruption 3000 years ago.
Coelacanth museum, Numazu
Wasabi farm in Izu (90 min train & bus)
Toi gold mine (active until 1965) 90 min by bus