Sinŭiju, also spelled Shinuiju, is a city in North Korea.
It is possible to get within a few hundred feet of Sinuiju by boat from Dandong. Various tour boat operators along the Yalu River surrounding the Friendship Bridge charge ¥20-50.
In wintertime, the river freezes over and locals on both sides trek across the border to trade (or defect). However, the North Korean army regularly patrols the border, and any foreigners caught on the wrong side can expect to be detained and accused of spying.