At exactly 12:30 they came, striding smartly to the thin tap of a tom-tom. They carried hand-colored flags -- "Peace, Justice," "Disarm," "No Intervention in Nicaragua" -- and as they poured down the steps toward the Reflecting Pool they were met with open arms and kisses and applause.

Twenty-eight Pilgrims for Peace, Europeans and Americans alike, had set out from Bangor, Wash., last May 1 to walk across the country, and yesterday afternoon they arrived at the Lincoln Memorial. About 100 people were there to meet them, and so was an amazing exhibit of 10,000 photographs, taped end to end in a plastic envelope that accordioned around the pool in a zigzag line.

If the line had been straight it would have gone around the pool many times, for it was 1 1/2 miles long. The frieze of pictures showed the 65-mile human chain that reached from Ulm to Stuttgart in West Germany just over a year ago, a chain formed by some 200,000 people protesting American missiles in Germany.

"The people of Europe see only the America that appears on television," said Inge Langen of Munich, a stage and TV actress. "But we feel that there is another America, an America which is as concerned for peace as we are."

The march across the country brought travelers from many European countries into direct contact with Americans, from Nebraska farmers to Chicago ghetto residents. The idea was to raise consciousness and show solidarity among people who oppose policies that accommodate nuclear war.

"We were told that it was the wrong time to do this," said Langen, one of several German women coordinating the project, "that there was the election and Nicaragua and so on. But we have to start. We have to cry out when we see the policy change so quickly from defense to a first-strike policy. If this isn't stopped, the whole of Europe will turn to communism."

As the marchers joined hands with local members of the peace movement, a succession of speakers called for an end to the missiles, to the maneuvers that crowd the German highways "300 days in the year," to the belligerent posturing by the superpowers.

"We are responsible for the future," one mother said. "Our children will ask us one day -- if they are there to ask -- 'Where were you when they prepared a nuclear war before your eyes?' "

The weaving of the web, a tradition at peace rallies, began as dozens of balls of colored yarn were tossed here and there, finally enmeshing everyone in a happy tangle. On the grassy bank rested a large banner: "Scandinavian Women's Peace March. Paris 1981. Moscow 1982. Washington 1983." A youth with a guitar sang a song he had written, then swung into "Ain't Gonna Study War No More," and the crowd followed.

"In this period of extreme danger," read the invitation being passed out, "when the future of all life on this earth is threatened with nuclear catastrophe, we come from Europe to share our fears concerning the arms race, our hopes for a solution, and our solidarity with those who work for peace in America."

Around the pool, a cutting wind rattled the strip of 8-by-10 photographs. They were taken by 45 students at the University of Essen, and they showed every one of the 200,000 who stood on that long line in Germany 13 months ago. It was a sunny day, like yesterday, and cold, for most of the demonstrators wore heavy sweaters, duffel coats, scarves.

You could walk along the line of pictures, letting the faces blur past, or you could move in close and study them: young people in jeans, white-haired people with city coats and hats, children in strollers, papoose babies, kids on bikes, families, clumps of people talking, stiff rows of people lined up like soldiers, people standing in front of gas stations and banks and apartment buildings, on the bleak shoulder of an autobahn, at the edge of a meadow.

In many places the people resolutely held hands. It is curious how people, when they are holding hands in a chain, tend to glance sidelong down the row, to one side and then the other, as if to confirm that they really are here, really part of it, really connected.

You could sense that connection yesterday, reaching somehow from the people in the pictures to the pilgrims as they arrived, and beyond them, in the mind, to the distance they had walked, clear back across America, across the continent. All those sidelong glances.