From Tokyo station to Shuzenji station by JR "ODORIKO Line", about 2hours 15minutes.
From Tokyo station to Mishima station by JR "SHINKANSEN KODAMA" ,about 1hour. From Mishima station to Shuzenji station by " IZU-HAKONE TETSUDO LINE" ,about 35 minutes.
From Shuzenji station to Arairyokan, take taxi or bus,  about 10 minutes.