This is the San Francisco public transit map.
Actually, this is the zoomed in version; the proper version is even more hideous and boggling. San Francisco is the best connected city in the US I've been to, but it is the worst possible one to navigate. I travel a lot, I've visited a lot of places. I've become adept at working out public transit in places that don't have a lot of it, and deciphering maps in countries where I don't even speak the language. And it took me 4 years to finally crack this map.
San Francisco runs a lot of public transit, but it only intersects at a few key points, there are many different public transportation systems, and a lot of them have names that are all too easy for an unfamiliar tourist to confuse. There's the buses, the various cable car routes, the old F trolley, the trams, the MUNI trains, the CalTrain, Amtrak, the AC Transit, the SamTrans if you go far enough and the Transbay Terminal which incoprorates some, but not all, of the above. Not all of them run the same ticketing system (improved in recent years by the Clipper Card), and not all of them run the same fares - the BART for example operates on a distance fare method, so 'season tickets' in the standard way don't really exist, but it does accept clipper, which does run a season ticket, but the BART clipper season ticket is only valid within the SF area, not its full route - confusing huh?
The SF transit map suffers from a problem of trying to display everything at once - this is partly necessary given how little area the Trolleys, MUNI trams & BART trains actually cover outside of the downtown area, huge swathes of San Francisco would simply fail to exist on a map that only included these routes - for example the Golden Gate Bridge is only accessible on public transit by one bus route within the city, and that bus doesn't go from the major tourist centers. But this means its virtually impossible to pick out a route. Added to this, many routes which run along the same roads are conflated together, so the route number might only be given once, and its not obvious where they run to or from. And depending on time of day or whether it's the weekend or not, your route may not run at all. It might get replaced by another similar route, or you might have to get there a different way altogether
If you know where you want to get to, where that is in relation to SF as a whole, and what major routes might be nearby to give you a starting point, then you're fine. The map is actually fantastic as it shows EVERYTHING, and you can see every possible connection and work out any number of crosstown routes. The top level monthly Clipper pass is $80, compared to ~$200 for the cost of a monthly Z1/2 travelcard in London. The efficiency of London bus stops showing you everywhere *that* stop goes to only, makes for easier immediate navigation, but means if you don't already know your connection, you have to guess where to pick it up; that's not necessarily in SF and the city runs an extensive night service along a lot of routes so no complaints there.
Also the bus route called the same thing regardless of whether it's headed inbound or outbound, which can mean you easily get on the wrong bus. One of the major upsides is the fact that so much of the bus routes are zero emissions by means of overhead wires which are installed throughout the ENTIRE city, which must of been a massive public works undertaking. The downside of that of course is buses can't really stray from their routes, and if one line down market street snafu's, they all do, and no-one's going anywhere till that problem is fixed.
It took me 4 years to learn the neighbourhoods, roads, and major routes of SF well enough to be able to properly utilize this map. As a tourist, you're probably stuck with the F line trolley or a cab, trying to get to Golden Gate Park, Golden Gate Bridge, Berkeley, the Palace of Fine Arts, the Presidio, Fort Point, Haight/Ashbury, Treasure Island, etc is just a nightmare. Mission Dolores is just a short walk from the Castro, which is doable, but beyond that, good luck!
On a side note - the problem with Uber compared to established (and heavily regulated) taxicabs is very apparent here. In London, to my experience, they have always been Addison Lee-esque. The cars are relatively top end, and new, the drivers are usually dressed smartly, it's much closer to a private limousine style cab rather than just a generic minicab service that whilst prebooked, is often just any suitable car and a driver. Here the Uber vehicles are basically any car for a driver registered with Uber, dressed how they like, and with a black Uber 'U' sticker in the front windshield. It doesn't feel very high class. And it certainly feels unregulated, which as a brit/european automatically makes me feel unsafe, whereas I'm sure plenty of Americans would happily extol the virtues of unregulated, 'free' industry.