Here is a generic image of an opium den from San Francisco ca. 1880 when the anti-Chinese/anti-opium movement was taking hold. And here is a photograph of an opium pipe saddle from Virginia City, ca.1890. The pipe bowl would have sat on top of the opening, and saddle would have been affixed to the wooden pipe, probably carved in the shape of a bamboo shoot. As you can see, there could be quite a bit of art associated with the paraphernalia.

One could expect a variety of types of opium dens in a place as large as San Francisco. The image shown here depicts the lower order of possibilities, catering to Chinese workers. For European Americans, some finer options would no doubt be available, but poorer addicts would probably go to something like this just as easily - and inexpensively.