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。
请问u-turn到底是不是合法的？
" J2 O7 a' A6 T6 u0 }2 R谢谢！

EightBelow

U-turns
• Do not make a U-turn unless you can do it safely and without interfering
with other traffic.
: Z3 o1 Y, @8 _/ U7 D0 ?$ Q• 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.
U-turns are not permitted in urban areas in the following situations:
; K" ~! }4 u# i/ C, b& y. q8 ^• On a roadway between intersections.
0 W: \, [( n& |• Where a sign prohibits making a U-turn.
• At an intersection controlled by a traffic-control signal (traffic lights).
7 H4 B( s) N! m8 H- o• At an alley intersection.

无语

有红绿灯的地方U-Turn是违规的。