Section 4. Whenever on any way, public or private, there is not an unobstructed view of the road for at least four hundred feet, the driver of every vehicle shall keep his vehicle on the right of the middle of the traveled part of the way, whenever it is safe and practicable so to do, except that the department of highways may alter this provision by the use of restrictive pavement markings in areas of limited sight distance, at intersections and at obstructions in the highway, on state highways, on ways leading thereto and on all main highways between cities and towns; and may by permit, revocable upon notice, authorize cities and towns to alter said provision by the use of such restrictive pavement markings; provided, that such markings shall be in accordance with accepted standards of engineering practice; but, notwithstanding the foregoing provisions, every driver of a slow moving vehicle, while ascending a grade shall reasonably keep said vehicle in the extreme right-hand lane until the top of such grade has been reached.
Structure Massachusetts General Laws
Part I - Administration of the Government
Title XIV - Public Ways and Works
Section 2 - Passing Vehicle Traveling in Same Direction
Section 3 - Sleigh or Sled; Bells
Section 4 - Keeping to Right While View Obstructed
Section 4a - Driving Vehicles in a Single Lane; Motorcycles, Riding and Passing
Section 4b - Driving in Lane Nearest Right Side of Way
Section 4c - Heavy Trucks; Driving in Right-Hand Lane on Multi-Lane Highways
Section 4d - Standing or Parking of Motor Vehicle in a Designated Bike Lane
Section 5 - Penalty; Exceptions
Section 6 - Applicability of Rules of Road to Street Railway Cars
Section 6a - Stopping of Street Railway Cars for Passage of Fire Apparatus
Section 7 - Right of Way of Fire Engines, Patrol Vehicles and Ambulances; Obstruction; Penalties
Section 7a - Restrictions on Use of Ways Upon Approach of Emergency Vehicles
Section 7b - Operation of Emergency Vehicles
Section 7d - Moving of Vehicle Involved in a Crash From a Travel Lane
Section 8 - Right-of-Way at Intersecting Ways; Turning on Red Signals
Section 9 - Designation of Highways as Through Ways; Traffic Control Signs and Devices
Section 10 - Violation of One-Way Traffic; Civil Liability
Section 11 - Marked Crosswalks; Yielding Right of Way to Pedestrians; Penalty