If you're in Shizuoka City and want to get out into the countryside for a day or afternoon, Utsunoya is probably the best place to head for. Just half an hour on the bus from the city, it's as different as you can get, with hardly any buildings other than a couple of roadside stations (not actually stations; they sell food and souvenirs) , a temple, and a row of historic houses dating back to the 19th century.
To be completely surrounded by nature, take the Tsuta no Hosomichi hiking trail, which runs between the two roadside stations. It's not very challenging at all - I was in sandals and using a walking stick as I recovered from a broken leg - and provides a range of scenery to enjoy. There are orange orchards, sturdy trees with exposed tangles of roots, steepish climbs through a forest of tall, straight trees, and attractive, distinct panoramas from each side of the summit.
Getting there
To reach Utsunoya, take a bus on the Chubu-Kokudo route from Shizuoka station, and get off at the Utsunoya-Iriguchi bus stop, about a 30-minute ride. This puts you by the larger of the two roadside stations: the western start of the trail is next to the station.