Washington’s landscape is undergoing its seasonal transformation. As if by elfish magic, evergreen trees appear, and studding the scene with twinkling lights. Last night, Union Station’s tree flickered awake inside the train station’s main hall. More lightings are scheduled this weekend and are set to shine through December.

Already lit:

City of Alexandria’s Christmas Tree (Market Square, 300 King St.). Strings of lights and other holiday decorations drape Old Town’s streets and storefronts. The light-drenched tree in Market Square finishes off the festive feeling.

Reston Town Center’s Christmas Tree (11900 Market St.). Make a penny wish into Reston Town Center’s fountain, ice-skate, or just rest in the light of the evergreen at the intersection of Market Street and Fountain Square.

Norwegian Christmas at Union Station (50 Massachusetts Ave., NW). Norway supplied the 32-foot Christmas tree, which stands in Union Station’s Main Hall. Head to the West Hall to see the Norwegian Holiday Model Train display.

Set to light Saturday, December 1:

Celebrate the Holidays in Del Ray (Mount Vernon and Commonwealth aves., Alexandria). Enjoy caroling and shopping during the day, then as 6 pm approaches, walk along the luminaria-lined Mount Vernon Avenue for the tree lighting.

Jingle Jubilee (City Hall Pavilion, 31 South Summit Ave., Gaithersburg). Jingle Jubilee starts at 6 pm, and the first 600 children will receive free jingle bells. Gaithersburg high schools and elementary schools will provide choral entertainment, and popcorn and hot apple cider will be served, all in expectation of a firetruck-riding Santa and the tree lighting.

Herndon Christmas Tree Lighting (Town Hall Square, 730 Elden St.). Beginning at 5 pm, join in the carols at a free holiday concert led by Herndon High School’s band. After the tree is lit, Santa will arrive in a red firetruck and hand out candy canes.

Set to light Sunday, December 2:

Crispus Attucks Park (along U, First, V and North Capitol sts., NW). This Bloomingdale neighborhood-run event starts around 4:30 pm; the tree will be lit by 5. Neighbors are invited to bring extension cords and twinkle lights to drape throughout the park, and all are welcome to bring a mug for hot apple cider.

Georgetown’s Holiday Tree (Washington Harbour, 3000 K St., NW). From 4 to 7 pm, decorated boats will float in from Alexandria. Holiday music, free Santa pictures and Starbucks coffee, special menus at harbor restaurants, and the lighting of Georgetown’s 26-foot tree as well as surrounding trees at 6 pm.

Set to light Wednesday, December 5:

Capitol Christmas Tree (west lawn of the US Capitol). Donated by Vermont, this 55-foot balsam fir is known as “the people’s tree” and will be lit this year by speaker of the House Nancy Pelosi at 5 pm. In addition to lights, the tree will wear 4,500 handmade ornaments.

Set to light Thursday, December 6:

National Christmas Tree and the Pageant of Peace (15th and E sts., NW). All 28,000 free tickets to the lighting have been distributed, but you can visit the LED-lit, 40-foot Colorado spruce tree anytime thereafter. Make your way to the tree by first trailing through the 56 smaller trees, which represent America’s 50 states, five territories, and the District of Columbia.