COLOGNE, GERMANY ? Pope Benedict XVI traveled in his popemobile to the rain-soaked Marienfeld, a former coal mine near the town of Kerpen outside Cologne for an outdoor evening service as part of the four-day Catholic youth festival.

Hundreds of thousands of high-spirited pilgrims roared their approval as Benedict arrived in his mother-of-pearl Mercedes-Benz, waving and smiling as he greeted the crowds, estimated at some 800,000. Overhead, as if on cue, storm clouds that had threatened to drench the faithful began melting away, unveiling a bright blue sky.

Before giving his homily, Benedict dedicated a huge bell at the foot of the altar to his predecessor, Pope John Paul II, the man who originated World Youth Day as a Roman Catholic festival. As it tolled, a choir performed a slow hymn while the crowd sang along.

Officials said people began arriving at Marienfeld as early as 9 a.m. to stake out their places, unfurl tarps to cover the wet ground and await the pope. Pilgrims were given candles, which they lit as darkness fell.

One person broke out of the crowd as the pope arrived and was tackled by several security guards about 150 feet from Benedict’s armored vehicle. Security officials at the vigil declined to comment on the incident.

In his homily, Benedict told the pilgrims that only religion can truly make people free.

Many pilgrims at the vigil were expected to spend the night under the open sky to attend this morning’s concluding Mass celebrated by Benedict.

– Associated Press writers Matt Moore and Melissa Eddy in Kerpen contributed to this report.