PRIPYAT, Ukraine - Sometime after visiting the ruins of the Polissia Hotel, the darkened Energetic theater and the idled Ferris wheel, the minivans stopped again. Doors slid open. Six young Finnish men stepped out and followed their guide through a patch of temperate jungle that once was an urban courtyard.
Branches draped down. Mud squished underfoot. A cloud of mosquitoes rose to the feast. The men stepped past discarded gas-mask filters to the entrance of a ghostly kindergarten. They fanned out with cameras and began to work.
Much was as the children and their teachers had left it 19 years ago. Tiny shoes littered the classroom floor. Dolls and wooden blocks remained on shelves. Soviet slogans exhorted children to study, to exercise, to prepare for a life of work.
Much had also changed. Now there is rot, broken windows, rusting bed frames and paint falling away in great blisters and peels. And now there are tourists, participating in what may be the strangest vacation excursion available in the former Soviet space: the package tour of the Chernobyl exclusion zone, scene of the worst civilian disaster of the nuclear age.
A 30-kilometer, or 19-mile, radius around the infamous power plant, the zone has largely been closed to the world since Chernobyl's Reactor No. 4 exploded on April 26, 1986, sending people to flight and exposing the Communist Party as an institution wormy with hypocrisy and lies.
For nearly 20 years it has been a dark symbol of Soviet rule. Its name conjures memories of incompetence, horror, contamination, escape and sickness, as well as the party elite's disdain for Soviet citizens, who were called to parade in fallout on May Day while the leaders' families secretly fled.
Now it is a destination, luring people in.
"It is amazing," said Ilkka Jahnukainen, 22, as he wandered the empty city here that housed the plant's workers and families, roughly 45,000 people in all. "So dreamlike and silent."
The word Chernobyl also long ago became a dreary, shopworn joke, shorthand for contaminated wasteland. But contamination here is uneven. And most of the zone is far cleaner than it was in 1986, when radiation levels were strong enough in places to kill even trees.
A lethal exposure of radiation ranges from 300 to 500 roentgens an hour; levels in the tour areas vary from 15 to several hundred microroentgens an hour.
A microroentgen is one-millionth of a roentgen, and Chernobylinterinform, the zone's information agency, says its chaperoned tours do not carry health risks. Dangers lie in long-term exposure.
Still, the zone has many more radioactive spots than those where tourists typically go. So there are rules, which Yuriy Tatarchuk, a government interpreter who served as the Finns' guide, listed.
Don't stray. Stay on concrete and asphalt, where exposure risks are lower than on soil. Don't touch anything. (This one proved impossible. Tours involve climbing cluttered staircases and stepping through debris. Handholds are inevitable.)
No matter its inconveniences or potential for medical worry, the zone possesses the allure of the forbidden and a promise of rare, personal insights into history. Its popularity as a destination is increasing. Few tourists came in 2002, the year it opened for such visits, according to Marina Polyakova, of Chernobylinterinform. In 2004 about 870 arrived, and an equal number is expected this year, she said.
One-day group excursions cost from $200 to $400, including transportation and a meal.
The tour on Saturday began with a drive through meadows, marshes and forest, a belt of green broken by glimpses of gap-roofed houses and crumbling barns.
It is what Mary Mycio, a Ukrainian-American lawyer in Kiev and author of a soon-to-be published book, "Wormwood Forest: A Natural History of Chernobyl," calls a "radioactive wilderness," an accidental sanctuary populated by wolves, boars and endangered birds. Its beauty cannot be overstated.
Soon reminders of the grim history appeared. The tour stopped at a graveyard of vehicles and helicopters used to fight Chernobyl's fires.
Roughly 2,000 radioactive machines are parked here - fire trucks, ambulances, armored vehicles, trucks, aircraft. Two tourists slipped through the barbed wire and wandered the junkyard, taking pictures for a Web site they plan to make of the trip. The rest roamed the edge, awed.
"I cannot find words," said Juha Vaittinen, 22.
The minivans then headed to Chernobyl proper for a briefing on the accident. Next stop: the nuclear plant and "sarcophagus," the concrete-and-steel shell built to contain Reactor No. 4's radioactive spew. Tatarchuk held up a radiation detector - 470 microroentgens an hour.
The Finns posed for a group shot.
The most popular destination came last: Pripyat, a city left behind.
"Heralded as the world's youngest city when it opened its doors in the mid-1970s," Mycio writes in her book, "Pripyat also turned out to be its shortest lived."
The city was encased on this day in a silence broken by breezes sighing through rustling trees. A heavier hush resided in buildings, where drops of water plopped loudly into puddles, and glass squeaked as it broke underfoot. Built on marshes, the place smelled of peat.
Its contamination has become uneven. At the amusement park, near idled bumper cars, Tatarchuk's monitor registered 144 microroentgens an hour. He moved a meter away, to a mat of damp green moss. It read 823. "Stay off the moss," he said.
The moss is all around. Pripyat, both a time capsule of the Soviet Union and a monument to its folly and pain, is being consumed. What looters have not sacked or stolen succumbs now to the elements and to time.
A café patio atop the Polissia Hotel, offering views to the reactor that ruined this place, has been colonized by birch trees. One stands roughly two meters tall, climbing skyward from a crack between the high-rise's tiles.
Fine views of Pripyat are available from among these misplaced trees, including one in the direction of the reactor that reveals an empty clinic bearing an enormous sign.
"The health of the people," it reads, "is the wealth of the country."
Tatarchuk, looking down over buckling rooftops, repeated those words in Russian, then allowed himself a knowing, head-shaking smile.