Turns to avoid
The above is how Apple Maps in iOS 6 renders a pretty busy interchange: Central Expressway at San Tomas Expressway. They get the names right, all of the connecting roads are there, and they even put the right road (Central) on top.
There's just one tiny little problem.
Neither of the circled spots are usable for traffic. If you're in a car and try to use either of those ramps, you're going to have a supremely bad time. Why? Easy. They aren't actually open, and haven't been for a very long time -- longer than I've been living here, for sure.
Here's a look at what you see if you're going west (left) on Central and want to go north (up) on San Tomas:
If you're dumb (or awesome, funny how that works) enough to drive off the main roadway surface, bounce over the telco access hole, and smash through the fence, you immediately encounter something else:
That appears to be some kind of reinforcement for a vault cover. I'm sure it's very heavy and solid and would make an even bigger mess of your car than all of the other obstacles.
Now, that said, if you somehow managed to get past all of those, you would in fact reach San Tomas. The rest of the ramp appears to be in a usable, if neglected, state, and you could pop out down there and freak out a bunch of unsuspecting drivers.
The other ramp (coming from San Tomas) also has a nice little surprise for you. Right at the beginning of that ramp, someone (probably the county roads department) put a storage shed in the middle of the road. No, I am not kidding. Look:
You'll notice I stood behind this one to get the picture, since standing in front of it would have put me in the middle of San Tomas.
But, hey, if somehow you manage to go around, over, or through (!) the shack, you wind up on a ramp which still exists and seems to be just fine.
Google maps, Bing maps, and Mapquest do not show these connectors. OpenStreetMap shows them as some kind of trail or track but definitely not a road. Apple stands alone.
Go on, crash through those barriers. Your GPS said so.