PORTSMOUTH, N.H. — The Memorial Bridge between Maine and New Hampshire will be closed for the next four nights for machinery and guide rail adjustments.

The bridge will be closed to all traffic — vehicle, bike and pedestrian — from midnight to 5 a.m. Monday through Friday morning. From 7 p.m. to midnight on those nights, traffic will be restricted to one alternating lane in each direction.

The new bridge connecting Portsmouth to Kittery, Maine, opened in August, replacing the original built in 1923. The final phase of illuminating the bridge is scheduled for completion in the first quarter of 2014.