Oga

Oga (; oga-shi) is a city in western Akita prefecture. The city covers a large peninsula -- the Oga Peninsula (男鹿半島; oga-hantō).

Understand

The JR Oga train line connects Akita and Oga, by way of Katagami City.

Like most of Akita, a car is very convenient. While there are some buses, they run infrequently and may be impractical.

Goshado (五社堂), 39.870701°, 139.750910°. This set of five shrines overlooks the coastline.
Akagami Shrine (赤神神社), 39.865361°, 139.752182°. This shrine is the starting point for the hike to Goshado.
Namahage Museum (男鹿市役所なまはげ館), 北浦真山字水喰沢９９９９ (go generally west by car from Oganaka; there are many zigzagging roads, so use a map), 39.929255°, 139.766687°, +81 185-22-5050. 08:30-17:00. This is a museum about namahage, the demons that scare children in Akita every New Year's Eve. Adults ¥500, kids ¥250
Oga Aquarium GAO (男鹿水族館GAO), 戸賀塩浜字壷ケ沢９３, 39.942213°, 139.704539°, +81 185-32-2221. Mar-Oct 09:00-17:00, Nov-Feb 09:00-16:00, Golden Week and Obon 08:30-18:00. Akita's only aquarium. Adults ¥1,000, kids ¥400

Shinzan Trail. This hiking trail goes from the Akagami Shrine to the Namahage Museum. It goes near the summit of Mt. Honzan (本山), which makes for a short side venture. The trail takes around 4 hours, one way, and bus service at either end is infrequent. Free
Namahage Sedo (なまはげ柴灯). 2nd weekend in February, Friday-Sunday, 18:00-19:30PM. This namahage performance involves demons coming down from the forest to scare children. There is also dancing, drumming, and mochi throwing.

Miyazawa Kaigan Auto Campground (宮沢海岸オートキャンプ場キャンパルわかみ), 野石字大場沢下１−７８, 40.03762°, 139.922755°, +81 185-22-8222. Check-in: 14:00, check-out: 10:00. This resort and campground is rather expensive, but it is well-situated on the beach in northern Oga. There are campsites and cabins, and also an onsen for bathing. Car sites for ¥6,000 per site; non-car sites for ¥4,000 per site; open camping area for ¥2,000 per tent

The capital city Akita is just to the SE. From Akita, there are many travel options in and out of the prefecture.