I visited the East Pole Islands (Dongji Dao) last year, and Yushan Island just recently. I have been all over China and these two trips were two of my travel highlights in the country last minute China travel deals. While the beaches are not great or non-existent (see below), the islands still have clean blue water, blue sky, amazing views, fresh air, etc.
To get to the East Pole Islands, you need to get to Banshengdong Wharf in Shenjiamen, Zhoushan Island. The best way to do this is to take the direct coach bus from Hangzhou Yellow Dragon Stadium tourist center (~4 hours), although there are also buses from Ningbo, Shanghai, etc.
Once in Shenjiamen, you need to get a permit from the police station the day before you head to the east pole islands. You need a permit to visit the islands as a foreigner because these islands are the furthest east you can go in China, a "border area" that has lots of sensitive military operations going on. Even Chinese visitors need to register once on the islands. Without the permit, you will be found and kicked off the islands on the next boat back to Zhoushan. Getting the permit is a piece of cake though.
The boat to the East Pole Islands leaves every day at 8am - 8:30am. There is also an afternoon boat (~1-2pm) on weekends and holidays. The boat ride takes 2.5 hours and everyone pukes due to the waves. I suggest getting a sleeper ticket so you can enjoy the bunks down below and not have to watch everyone puking. Boats are canceled if there is a typhoon best tours of China.
There are 4 East Pole Islands, 3 of which you can visit. The boat from Banshengdong Wharf takes you to Maozihu island, the main island with Dongji Town, hotels and restaurants, plus a small temple and a naval base. There is also a bar run by a Shanghai person.
Once on Maozihu, you can take smaller boats to the other islands: Qingbang and Dongfushan. Dongfushan is the furthest east and most beautiful. At Qingbang and Dongfushan, you can only stay at "fisherman's homes" but this is standard and lots of tourists do this. Dongfushan is the best place to see the sunrise and also has a small beach (beware of sharks and jellyfish).
There used to be a helicopter that ran between Zhujiajiao popular China tour package (next to Shenjiamen) and the East Pole Islands. This is temporarily suspended after a Japanese tourist on the helicopter photographed naval drills near the islands. The helicopter is supposed to start up again within the next year or two and takes just a few minutes to get to the islands, but is expensive.
3 days and 2 nights in enough for all 3 islands.
Yushan Island is more or less due east of Taizhou off the coast of Zhejiang, still in clean blue water. Yushan Island has a much less developed tourist infrastructure, but does have some hotels and a cool lighthouse. There is also a tunnel system under the island from the Sino-Japanese wars. Most tourists on Yushan island camp there. There is also a north Yushan island with no buildings at all.
To get to Yushan Island, you first need to get to Shipu town, in Xiangshan, Ningbo Yangtze River tour. There are direct buses from Ningbo, Hangzhou, Ninghai, and Shanghai to Shipu Town. Hangzhou to Shipu is a little over 3 hours. From Shipu, boats leave to Yushan Island from Yanchang Wharf. There are no regular ferries and you have to hire a fishing boat, hopefully with 10+ other people to share the cost. But there are boats headed to Yushan island every day, and you can probably squeeze onto one that was booked by a tour group. 2 full days and one night is all you need for Yushan. I went swimming off the rocks but there are no beaches. Be careful of barnacles if you swim off the rocks.
Do check out these islands, they are way better than the tourist trap of Putuoshan and a nice break from the crowds, pollution etc of many more popular travel destinations in the area.
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