From the New York Times (link):
Karl Marx‘s birthplace is a stately three-story house that has been a fixture of this ancient town on the Mosel River since it was built in 1727. What is changing are the large groups that visit almost every day from China, one of the few countries in the world still under the control of something calling itself a Communist Party.
Chinese tourists have started to become common in Europe as China has become richer and tourist agencies have sprung into action. Trier is a worthy destination by any standard, having impressive and important Roman ruins as well as an 11thcentury cathedral built in the very place where Emperor Constantine‘s mother first built a church in the fourth century.
But the Chinese clearly come to see the place where Marx was born in 1818, and the local authorities try to take full advantage of it, promoting their city in China itself and with the travel agencies that serve Chinese tourists.