San Pedro Prison occupies a large block in the neighbourhood of the same name, about fifteen minutes' walk south of Plaza Murillo. From outside it looks like what it is: a high-walled compound with a gate and guards. What you cannot see from the street is the internal life — the families who lived inside with inmates for years, the restaurants and shops operating in the courtyards, the real estate market for cells, with better accommodation costing more per month. The internal economy was not a metaphor or a journalist's simplification; it was the literal operating system of the prison.
The informal tourist access that made San Pedro famous — foreign backpackers paying inmates for tours, buying cocaine, staying for dinner — was shut down in the early 2000s after diplomatic pressure, and the prison has tightened since. You will not get inside on an informal visit today. But the building is still there, still operating in its idiosyncratic way, and worth walking past if you are in the neighbourhood. Read Marching Powder before or after — it is a genuinely strange and specific book, and La Paz looks different having read it.