RSA 265:16 Drive on Right Side of Roadway; Exceptions.

I. Upon all roadways of sufficient width a vehicle shall be driven upon the right half of the roadway, except as follows:
(a) When overtaking and passing another vehicle proceeding in the same direction under the rules governing such movement;
(b) When an obstruction exists making it necessary to drive to the left of the center of the way; provided, any person so doing shall yield the right of way to all vehicles traveling in the proper direction upon the unobstructed portion of the way within such distance as to constitute an immediate hazard;
(c) Upon a roadway divided into 3 marked lanes for traffic under the rules applicable thereon;
(d) Upon a city street designated and signposted for one-way traffic.
II. Upon all roadways any vehicle proceeding at