Some tour operators offer small bags of bread and biscuits for sale, which tourists can throw onto the shore for border guards and children to eat.
For many in China, the fascination with North Korea extends to more than just it's isolation, there are historical parallels.
"I think it looks a bit like China in the 70s or 80s, it's the first time I've seen this and I feel their economy is not very developed, but it looks like they're doing their best to build it up," said tourist Lu Mingyang as he squinted through binoculars looking into Sinuiju.
But in recent months, changes have come to Dandong as relations between the two sides have soured. Fishermen dotted along the border used to trade freely with their counterparts on the North Korean side. Now, following wave after wave of sanctions, it's been driven underground.
"There's definitely still secretive trading, we're so close and if you have a boat then you're definitely going to do a bit, it's definitely happening," said Captain Ma, known to his fellow fishermen as Big Ma, though he insisted he and his crew did not trade with the North Koreans.
Perhaps the clearest symbol for the cooling in relations between the two sides is the gleaming new Yalu River bridge, often referred to in the media as the bridge to nowhere.
Towering above the murky waters, the New Yalu River Bridge was supposed to symbolise a new era in relations between China and North Korea, helping bring investment to landmark free trade zones jointly run with the impoverished and isolated state.
Costing 2.2 billion yuan and partially completed in 2015, the dual-carriageway bridge today sits abandoned, the impressive border post on the Chinese side deserted and locked, not a soul to be seen. On the North Korean side, the bridge ends abruptly in a field.
"China fulfilled its promise and built the bridge but ever since then, it's been impossible to build the motorway on the North Korean side. A very important reason why it was never built is that North Korea repeatedly tested missiles and China supported the United Nations and passed resolutions for sanctions so relations between the two countries chilled," said North Korean expert Cheng Xiaohe.
Even following North Korean Leader Kim Jong-un's surprise visit to China, it was unlikely the bridge would be opened any time soon, said Cheng, as the process of North Korea abandoning its nuclear weapons program and diplomatic relations being restored is likely to be a long one.
As night falls, the difference between Dandong and Sinuiju becomes most stark. The Chinese city is ablaze with neon lights, and lit-up homes. By comparison a few lonely windows glow from Sinuiju, with chunks of them being knocked out by what appear to be power cuts.