Hong Kong was a large city located in China.
During the 2012 apocalypse, Hong Kong was hit by massive earthquakes, destroying many of its buildings and landmarks, killing numerous people. The state of China moved from its original position to where the Pacific Ocean was when the Earth's crust shifted more than a thousand miles. The ruined and devastated Hong Kong was then swept by a megatsunami at the height of 1500 meters in the Worldwide Flooding.
After the apocalypse ended, Hong Kong and the rest of China is submerged underwater, left with extreme damage and is rendered uninhabitable.