The Nighttime's the Right Time to See D.C.

Washington at night is austere in a way it is not during the day, under the glare of the sun. As the sky turns from blue to purple and finally black, Jefferson seems to stand taller, Lincoln to clench his fist tighter, the Vietnam Veterans Memorial to sink lower.

But when was the last time you actually noticed that?

This weekend, see a Washington you normally miss with the Bike and Roll Sites@Nite tour. The tour starts behind the Old Post Office and hits many of the hot spots on the Mall, from the World War II Memorial down to the Lincoln Memorial, through West Potomac Park to the Jefferson Memorial.

The bikes are equipped with lights, and riders wear reflective vests. Aside from about five minutes in the beginning, the tour stays on sidewalks. The Trek bikes are new every year and come with a water bottle and helmet. Trailer carriers are available for young kids. With one guide in the front of the group and one in the back, safety is their biggest concern, our tour guide, Jas Guram, 24, reminded us often.

The tour is four easy and slow miles, round trip, with a maximum of 15 riders per trip. Make sure you ride your bike around on the patio before you start out so a guide can adjust your bike seat if necessary. You can leave bags at the meeting place. Another tip: Bring bug spray; you may have to bike through whole clusters of mosquitoes cruising next to the Potomac River en route to see Mr. Jefferson.

But the tour is not just about riding and reflecting on the beauty of the city's night sky; it's also about boning up on your D.C. facts before the onslaught of relatives this summer. Do you remember how old the designer of the Vietnam Veterans Memorial, Maya Lin, was when she entered her proposal? Do you know the reason the World War II Memorial was opened to the public before it was dedicated? Can you recall why it is that you can view the White House from the Jefferson Memorial? The guide talks about every important place before allowing time to look around.

Richard Behar was visiting from New York with his family. Behar, a journalist, said he had been to Washington often for work, but it had "been years since I've done this sort of thing. It seemed perfect: the monuments at night, outdoors. You can't miss."

One of the greatest things about the bike tour is its efficiency.

"It would take two or three days to do all the stuff we did in a couple hours," Matthew Dalimonte, 12, said after the tour. Visiting from Massachusetts with his mom, dad and two younger brothers, Matthew decided that the bike tour was one of his favorite activities.

Most of the bikers on my trip were tourists, but that is not always the case, Guram said. He knows there are people living in the area who drive past the Lincoln Memorial all the time "and never go in." The tours are for them, too, he said.

-- Moira E. McLaughlin

What's it cost? Adults, $45, kids 12 and younger, $35. Call 202-842-BIKE or go to http://www.bikeandroll.com. Tours run every evening, 6:30-9:30, except Wednesdays. Starting May 23, Bike and Roll will also begin offering a Capital Sites@Nite tour at 6 every night except Wednesdays. This tour covers more ground and doesn't allow time for walking around.

Where is it? Across from the Federal Triangle Metro station, 302 12th St. NW. The group meets in the courtyard behind the Old Post Office. Get there early to get set up with your bike.

If you have more than three hours? Grab a drink or a late-night bite at Old Ebbitt Grill, 675 15th St. NW. Food is served until 2 a.m.

Want more night biking? Saturday at 8, meet at PAC HI Hostel at 11th and K streets NW and pick up a route sheet for a 15-mile Moonlight Memorial Monument Ride. It's free, but donations to the Potomac Area Council of Hostelling International are suggested. BYOB (that's bring your own bike).