the Wall came closest to the domestic buildings in the East, and many escape attempts occurred there. A portion of the Wall has been rebuilt, complete with the “death strip” between its parallel heights of concrete and barbed wire. A documentation center, with photographs and personal accounts, opened there in November 1999, on the tenth anniversary of the fall of the Wall.

In the last Cold War years, as the authority behind the Wall was crumbling, a whole school of art with a flip, cartoony style grew up on its Bernauerstrasse stretch. Its bestknown practitioner was the muralist Thierry Noir. Some of those images are now preserved, barely, at the East Side Gallery on Muhlenstrasse, on the east bank of the Spree.

To see the famed guardhouse at Checkpoint Charlie, you must take the subway to the Allied Museum near the U.S. Embassy complex, in southwest Berlin. That museum gathers artifacts from the decades of the Allied occupation along with its own piece of the Wall, a cargo plane from the airlift, and a guard tower. It also has part of the lining of the tunnel that the CIA dug in 1960 to penetrate the east to tap phone lines. The day I visited, a special exhibition was up of items relating to Francis Gary Powers and the U-2 incident of that year.

The display had been put together by Francis Gary Powers, Jr., from the collection he is assembling for his planned Cold War Museum. A few weeks later I stood with Powers in front of a crumpled chunk of the U-2 his father had flown. We were in the National Cryptologic Museum in Maryland outside Washington, around the corner from the National Security Agency, the famed “puzzle palace” dedicated to breaking codes and eavesdropping. After attending an international conference on the Cold War in 1995, Powers conceived the idea of creating a Cold War Museum in Washington to honor his father and all Cold War veterans. He envisions its including a U-2, a section of the Berlin Wall, a KHIl spy satellite, a fallout shelter, and other artifacts.

One way he’s assembling funds for it is through the Spies of Washington Tour, led by him and two former intelligence operatives named Carol and John Bessette. My fifteenyear-old daughter and I joined one of their excursions recently. We boarded a bus in a Pentagon parking lot and headed off with Mrs. Bessette as guide. At one point, she asked who among us remembered duck-and-cover exercises. About half the hands went up. My daughter hadn’t heard of them, “but,” she supplied, “we have practices like that too, in case of a Columbine-type incident.”

We passed the house of Aldrich Ames, who was apprehended in 1992 after having given secrets to the Soviets for more than a decade, and we saw the mailbox on which he used to leave a chalk mark when he wanted to meet his Soviet handler. In Georgetown we looked at

Alger Hiss’s house and stopped for coffee at a place called Au Pied du Cochon, where a former KGB operative named Vasily Yurchenko, lunching with his CIA handler in 1985, changed his mind and—the very word is Cold War—redefected.

In the middle of the meal Yurchenko went to the men’s room, apparently used a pay phone to call the Soviet Embassy, walked up Wisconsin Avenue, and turned in at the embassy’s iron gates. His defection and then redefection embodied a typical Cold War ambiguity: Which side was he ever really on? The restaurant has made the most of the episode, offering a plaque at the table where Yurchenko sat. My daughter snapped photos while I visited the men’s room and saw the phone. Neither of us, however, sampled the house drink, the “Yurchenko Shooter.”

Out West, a curious and wonderful organization called the Center for Land Use Interpretation (CLUI) often leads tours of Cold War sites. I went on one last fall to the expanses of the Nellis Air Force Base, a vast area of Nevada where pilots trained in exercises using MiGs and other aircraft. The state is also home to the Nevada Test Sites, the Tonopah Test Range, where cruise missiles and stealth fighters first flew, and the Groom Lake Test Facility, the mysteries of whose uses have made it notorious among flying-saucer conspiracy buffs, who know it as Area 51.

The nonprofit CLUI, based in Culver City, California, is headed by Matt Coolidge, who puts on photo exhibits and erects historical markers as well as conducts tours. Our tour was named Landscape of Conjecture because we still had to guess at the purposes and locations of many of the monuments.

With Coolidge’s guidance and a set of cleverly devised computer-generated maps, we learned that beyond the oblongs of desert out the window stood landmarks like a “smokey SAM” simulated anti-aircraft missile, a set of practice targets, and “Terrortown,” a village set up for practicing house-to-house combat. We saw an antique guided missile and the barracks of the first stealth pilots. At the Nevada Test Sites we rumbled along gravel roads past domed fallout shelters, test bridge abutments, and even a large bank safe that was exposed to blasts in the 1950s. Far off in the desert we caught a glimpse of a bunkerlike structure containing a subtle reminder that the Cold War may yet return.

It was the Device Assembly Facility (DAF), an extensive hulk with banked concrete sides, barbed-wire fences, and twin 50-foot watchtowers bearing mysterious antennas. The facility was designed for putting together nuclear weapons for testing, and it had just been completed, at a cost of $100 million, when testing was halted in 1991. A fellow tourist who had been inside told us that it looked like an action-thriller set, with chambers called “gravel gerties” designed to collapse and contain any accidental blast, and huge sliding doors, each of which had to close before

the next could open.

Amid recent discussions of an ICBM shield and changes to the Antiballistic Missile Treaty, the possibility has been raised of putting the DAF back into service. The question is whether it would be used to put warheads together or to take them apart. It hunches in the desert as a reminder that, though the Cold War may be over, it is not necessarily dead.