有关u-turn

小胡同

最近查google map for directions, 经常会看到需要u-turn。印象之中好像在主路上不可以，不管是否有不可u-turn的牌子。平常也看到有人在红绿灯处做u-turn。
8 V; X) F. R- T  q3 r! x2 ~! {请问u-turn到底是不是合法的？
谢谢！

EightBelow

U-turns
- _) j* ^1 A7 b: R; ~• Do not make a U-turn unless you can do it safely and without interfering
with other traffic.
• Outside urban areas U-turns are not permitted on a curve or near the
6 q/ m2 ~3 Y1 F) W: xcrest of a hill where the driver of another vehicle cannot see your vehicle.
6 Q( y1 q8 O9 B, M, f+ _U-turns are not permitted in urban areas in the following situations:
9 z, V+ t, p; ^7 B• On a roadway between intersections.
• Where a sign prohibits making a U-turn.
• At an intersection controlled by a traffic-control signal (traffic lights).
- H# @8 s# ?1 n, D• At an alley intersection.

无语

有红绿灯的地方U-Turn是违规的。