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。
/ R% L" H1 W1 n& s( ^1 {. X9 c请问u-turn到底是不是合法的？
1 I3 H' R0 x# H+ I9 v谢谢！

EightBelow

U-turns
• Do not make a U-turn unless you can do it safely and without interfering
with other traffic.
/ M' Q- x' }: g+ O9 d• Outside urban areas U-turns are not permitted on a curve or near the
1 g- {3 t7 ~$ ], x4 C( ~4 k# bcrest of a hill where the driver of another vehicle cannot see your vehicle.
: _5 C* F/ h% OU-turns are not permitted in urban areas in the following situations:
) H4 Z3 |1 w1 m: t3 I) G3 [• On a roadway between intersections.
0 v& z. M& n( K! S0 `• Where a sign prohibits making a U-turn.
8 E+ v* m/ [$ ^) \5 r• 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。