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。
. m2 n. I0 I! P8 h9 ^7 M请问u-turn到底是不是合法的？
谢谢！

EightBelow

U-turns
• 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
5 \% o8 u. `! u3 a% wcrest of a hill where the driver of another vehicle cannot see your vehicle.
7 h  S0 t6 _* z& O  fU-turns are not permitted in urban areas in the following situations:
1 {  o% q8 d. w4 a; X9 ^( n• On a roadway between intersections.
• Where a sign prohibits making a U-turn.
3 ]6 l# c" ]) g* [$ w• 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。