A major disruption on Metro’s Red Line through downtown D.C. is scheduled for this weekend, along with several events likely to draw crowds to the city.

The Metro weekend maintenance program calls for a suspension of train service between Dupont Circle and NoMa-Gallaudet University. A free shuttle bus service will be in operation, but the buses will be going through the heart of D.C., and that’s likely to mean a significant increase in travel time.

The work is scheduled to begin at 10 p.m. Friday and continue through the train system’s midnight closing on Sunday.

Meanwhile, the Nationals will be playing Friday night and Saturday and Sunday afternoons. The Nation’s Triathlon, which involves streets around the National Mall and continues up through Georgetown and along the Clara Barton Parkway, is scheduled to begin at 7 a.m. Sunday in West Potomac Park.

And the Adams Morgan Day Festival is scheduled for noon to 7 p.m. Sunday on 18th Street NW between Columbia Road and Florida Avenue.

Here are some more details about the Metro disruptions.

While there’s going to be work on the Orange and Yellow lines, the Red Line disruption will be the main event for transit riders. The Red Line is Metro’s most heavily traveled line, and the track work splits the line in two, affecting many of its busiest stations.

Between Shady Grove and Dupont Circle, and between Glenmont and NoMa-Gallaudet University, trains are scheduled to operate every 10 minutes between 9 a.m. and 9 p.m. Saturday and Sunday, and at regular weekend intervals at other times.

In between, the free buses will operate along two routes.

One route will go between Dupont Circle, Metro Center, Gallery Place and NoMa-Gallaudet University only. Metro estimates that a trip from one end to the other will add half an hour to normal travel times.

Another route will stop at all the affected stations. Don’t take this if you want to go the entire route, because Metro estimates it will take about 50 minutes.

The transit authority made a few suggestions about avoiding the disrupted area.

One option is to ride the D.C. Circulator buses along K Street NW. That’s the Georgetown-Union Station route. The buses are scheduled to arrive about every 10 minutes at numerous stops.

There are a variety of Metrobuses operating in this part of downtown. To figure out if a route will work for you, check the Advanced Trip Planner on Metro’s Web site and fill in the details about where you’re going and when.

A Nats fan who starts a trip on the east side of the Red Line would probably find it easier to transfer to a Green Line train at Fort Totten to reach the Navy Yard station near Nationals Park.

The trip I’m most concerned about is the one the fans will take at the end of Friday night’s game. The ones who use the Red Line will have arrived at the park under normal service conditions. But with the disruption starting at 10 p.m., the riders who take the Green Line north to the transfer point at Gallery Place would find that they had to board those shuttle buses to reach the open part of the Red Line.

Orange Line: Trains will share tracks through two work zones. One will be between East Falls Church and West Falls Church, and the other, between Stadium-Armory and Cheverly. Orange Line trains are scheduled to operate every 24 minutes, but add about 15 minutes for travel through a work zone, Metro says.

Yellow Line: Trains will share a track between Huntington and Braddock Road. Yellow Line trains will be scheduled to operate every 16 minutes, but add about 10 minutes for the work zone. The trains will terminate at Mount Vernon Square, rather than continuing north to Fort Totten, as they normally would on a weekend.