A little math:
What distinguishes the "angle" of "bias." Bias - a measure of the steepness of the slope, ie is the ratio of the excess area to horizontal extent at which it is observed.
The value of the slope is equal to the tangent of the angle between the surface of the slope and horizontal. If we draw a triangle with sides of 2 meters and 1 meter, then the angle is only 27 degrees, but the slope is 50%.
Parking on many streets permitted only at 90 degrees. Front passenger out of the car alone is very difficult (tried).
Sometimes you see only the sky, when you go up.
Street the most valuable and interesting in San Francisco
can be photographed so
to park and get under way at such biases is not easy.
Lombard Street, the most winding street in the world.
The design of the street was adopted to smooth the 27% slope "Russian Hill", on which it is located.
Street made one-sided, only the top down as hard to climb up on foot still on the machine.