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 J6 d$ [7 r- g$ w, m8 B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.
, |( U5 S" W0 I, @2 G• Outside urban areas U-turns are not permitted on a curve or near the
crest of a hill where the driver of another vehicle cannot see your vehicle.
  q) G! `; l  w7 W! R  P, NU-turns are not permitted in urban areas in the following situations:
• On a roadway between intersections.
& R- U8 S: F1 Q7 P& J• Where a sign prohibits making a U-turn.
# S5 A# C2 F3 O2 f+ g( a1 m• 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。