A huge station in the middle of downtown In the middle of downtown San Francisco sits a building that feels almost too big to be “just” a bus station. The Salesforce Transit Center stretches across several blocks, with a long rooftop park on top, buses moving through an elevated deck inside, and an mysterious empty box hidden below ground. That is what makes the place interesting. It is already a major piece of transport infrastructure, but it also feels like a building that’s still waiting for its most important function. What it does today For now, the Transit Center mainly works as a regio…