Minna-jima is a pleasant beach getaway, worth a visit but maybe not multiple visits.
Getting there/away
The ferry leaves from Motobu city's port. You can park right in front of town by the port and walk to the ferry departure point, which is close to the run-down playground fronting the water. There is a small booth selling ferry tickets. The ride is about 20 minutes. Upon purchase of the round-trip ticket, you are supposed to nominate the return time, but this does not appear to be strictly enforced.
Getting around
You can walk around most of the island on the beach. There is a cobblestone road that bisects the island, with dirt tracks coming off and leading to beaches. The main beach is right where the ferry docks. It is the prettiest, and has amenities like snorkel gear and umbrellas for rent. But if you want solitude, just wander and you'll find a spot for yourself.
Accomodations
We saw a place that looked like a hostel at the end of the road bisecting the island, but did not make enquiries.
We saw a place that looked like a hostel at the end of the road bisecting the island, but did not make enquiries.
Food
On island there are a couple places on the main road that sell cold drinks and beer, yakitori, yakisoba, and delicious ice cream in tropical flavors. The charge reasonable money. Bringing a picnic lunch also works.
Notably, one of Okinawa's most famous soba joints, Kishimoto, is in Motobu town, just around the corner from the market, on the same street as the place selling shaved ice on sweet red beans. Both places are always packed with Japanese locals and tourists, and are deserving of their reputations. The soba specialty with sweet pork is 450Y for a small bowl (a big meal) and the ice over red beans (a meal in itself) is approx 300Y.
There is also a place in Motobu town that specializes in Taco Rice. It is a classly looking place with dark wood tables, walls, and ceilings. The front has wooden crosshatching with little pieces of pottery and plants arranged artistically. No English menus, but the more expensive is hot taco rice with a crusty rice bottom (like bimibop), and the less expensive one is traditional lukewarm.
Fun
Japanese tourists do banana boat and jet ski rides. We snorkeled a bit -a decent number of colorful fish, but no live coral. We found a beach 1/3 the way around the island with a shade tree and just camped out there. The main beach has a covered area behind the sand with plastic tables and chairs and Orion for sale.
Cautions
At the end of the day the showers and bathrooms had a long line of Japanese tourists waiting to clean up and change before getting on the ferry.