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。
请问u-turn到底是不是合法的？
谢谢！

EightBelow

U-turns
: T$ `0 N3 k8 U' {$ I, R4 c• Do not make a U-turn unless you can do it safely and without interfering
2 ~: N, `% N) L% lwith other traffic.
+ B, _) o, q+ h) z4 U• Outside urban areas U-turns are not permitted on a curve or near the
: s% _+ l! W$ `, v  U& _/ jcrest of a hill where the driver of another vehicle cannot see your vehicle.
U-turns are not permitted in urban areas in the following situations:
• On a roadway between intersections.
• Where a sign prohibits making a U-turn.
• At an intersection controlled by a traffic-control signal (traffic lights).
• At an alley intersection.

无语

有红绿灯的地方U-Turn是违规的。