I think it takes at least two days to go to Changdao. If you must take a one-day trip, I suggest you go by
Penglai
Leave early and come back late. I recommend you to visit the two most beautiful places on Long Island. Namely: Jiuzhang Cliff at the northwest end of North Changshan Island, known as the “Fish Mouth”, and Linhai Fengshan Park at the southeastern end of South Changshan Island at the “Fish Tail”.
Jiuzhang Cliff should be regarded as the essence of Changdao’s scenic spots, with both natural landscapes and cultural and historical monuments. It is a seaside reef group formed during the crustal movement 100 million years ago, at the same time as the Yanshan orogeny and the Himalayan orogeny. On the southern slope of the cliff top, there are also ancient cultural relics from the late Shang and early Zhou dynasties called “Pearl Gate Cultural Sites” by archaeological experts.
Linhaifengshan National Forest Park is at the east end of Changdao. The best thing here is to see the boundary between the Yellow Sea and the Bohai Sea. Here is another experience. You can go down to the “Longwei” beach to watch. The waves of the Yellow Sea in the east surge to the west, and the waves of the Bohai Sea in the west rush to the east. The two waves meet each other. When struck, the water is surging, like thousands of armies confronting each other, thousands of horses confronting each other, or like two dragons mating, embracing and playing.
Yellow and Bohai Sea dividing line
Longwei Beach

Watch the two seas intersect up close

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