The MBTA will close several train lines for work periods in November as it strives to achieve its long-sought goal of improved service by the end of the year.

T officials said last November that by the end of 2024, they aimed to fix the nearly 200 slow zones that then plague the transit system. Each represented an area where the MBTA’s struggling infrastructure limited the speed at which trains could travel, lengthening travel times.

After extensive work throughout last year, only 16 slow zones remained at the end of October, MBTA data showed.

The upcoming closures will affect the Red Line and the Green Line Branches E and D as work crews tackle remaining maintenance projects.

For all closures, full details on alternative transit options, including free shuttles and commuter rail rides, are available at the MBTA website.

Red line

The Red Line will be closed between Broadway and North Quincy from November 5-10 for track work. On November 9 and 10, the closure will extend from Broadway to Ashmont.

Shuttle buses will transport passengers between affected stops, and commuter rail travel will also be free between Braintree and South Station during the closure.

From November 18 to 24, the Red Line will be closed between Harvard and Broadway for track work. Shuttles will replace rail service, but will not stop at Park Street or Downtown Crossing. Instead, passengers in those areas should board shuttles at the Haymarket or State stations, the MBTA said.

During the closure, commuter rail will also be free between Porter Square and North Station and between Braintree and South Station.

Separately, the MBTA said shuttle buses will replace Red Line service between Braintree and Quincy Center on the morning of Nov. 3 at approximately 2 p.m. for an “emergency training exercise.”

Green line

The Green Line E and D branches will not stop between Park Street and East Somerville the weekend of November 15-17 during track maintenance. The closure will begin at 8:30 p.m. this Friday and will last until Sunday.

The MBTA encouraged riders to take shuttles or use the Orange Line to travel between downtown stops.

From November 11 to 17, Branch D will be closed between Union Square and Lechmere for track work. The MBTA encouraged riders to use bus routes 86 and 91 to travel between Union Square and East Somerville.

Branch D will also be closed between Riverside and Kenmore November 9-10 to improve signal. The MBTA said passengers hoping to reach Union Square should instead take the C Branch, which will run trains between Cleveland Circle and Union Square.

Little by little, the extended closures allowed the MBTA to drastically reduce the volume of speed restrictions.

On Oct. 22, the agency reopened a large section of the Orange Line that had been closed for nearly two weeks for “critical” rail improvements. This work led authorities to lift train speed restrictions in 20 areas. The closure also allowed maintenance crews to upgrade the station’s signal systems, safety features and equipment, the MBTA said.

If repair crews had only worked each night when the subway system is normally closed, the huge backlog of T maintenance projects could have taken years longer, MBTA General Manager said this summer. Phillip Eng.

“There is a lot of catching up but I thank the public for their patience,” said Eng, who was nominated last year after holding senior positions in New York City public transportation, said. “Because at the end of this year, they will have a system that they can rely on better.”