SHENZHEN — Facebook’s apps and websites have been blocked in China for years. The company has no office in the country that supports its social networking services. And its attempts to open a subsidiary have been quickly snuffed out.

But here in the southern Chinese city of Shenzhen, Facebook has managed to quietly build a presence with the help of a local partner.

In Shenzhen’s Futian district, on the ninth floor of a concrete tower, there is an open-air sales floor that works as a sort of corporate embassy for the social network. The 5,000-square-foot space is run by the local partner, called Meet Social, but has been designed with Facebook’s guidance. It functions as an experience center for the Silicon Valley giant — the only one of its type in the world.

Its smallish size belies a crucial, and often overlooked, part of Facebook’s business. The center — which looks as if it fell out of Silicon Valley, with stenciled paintings of chat boxes on the walls, a lit-up heart icon and a pristine billiards table — hosts prospective clients and curious customers who wish to advertise on Facebook to reach the network’s 2.3 billion users, most of whom live outside China.