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。
6 f, x. s& Q, `7 L  |" P5 @& p9 k请问u-turn到底是不是合法的？
4 s' s/ _& ?" H( w谢谢！

EightBelow

U-turns
" t/ x6 x& ?6 S• Do not make a U-turn unless you can do it safely and without interfering
6 T% s4 t' @: p' q" Bwith other traffic.
/ Y# F0 v: m$ Z& L0 m. ?$ B• 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.
0 j% L& C6 B* o5 \2 d% X+ P- NU-turns are not permitted in urban areas in the following situations:
6 r! p7 E+ t2 W2 M6 f• On a roadway between intersections.
% u; Z$ E! j1 n" l0 s• Where a sign prohibits making a U-turn.
$ v9 a, v( M1 }* O* h• At an intersection controlled by a traffic-control signal (traffic lights).
+ Z5 X  `9 i3 ?$ }5 ^• At an alley intersection.

无语

有红绿灯的地方U-Turn是违规的。