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。
& O1 }1 b! c5 c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
; ?+ b. O3 L" R* w% B# D; J+ O0 R7 Iwith other traffic.
2 C3 a. {/ T' j& t9 U• Outside urban areas U-turns are not permitted on a curve or near the
( f0 F8 D! X1 y) ~1 F$ _5 u$ Ncrest 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.
0 e+ X7 ?, q( d6 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。