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。
3 N4 g6 x% E  P, P& c1 j; K) x请问u-turn到底是不是合法的？
7 b1 U: b$ o$ Z3 x- B/ O! x谢谢！

EightBelow

U-turns
  V( T0 c2 Y& r6 ?# R• Do not make a U-turn unless you can do it safely and without interfering
with other traffic.
6 _* N/ H7 a( l3 X4 K/ D• Outside urban areas U-turns are not permitted on a curve or near the
- O, Q) b& V. M" a! [4 i1 W/ f9 Xcrest 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.
% r4 g$ b; [9 ~8 O6 l" e0 s( }• 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。