Thousands stuck in U.S. as volcanic ash grounds flights

(NBC) – A massive ash cloud ground travel to a halt for the fifth day straight across much of Europe. The other side of the Atlantic is feeling the trickle effect in what now is being called the worst time for air travel since the 9/11 attacks.

Many Europeans were in Washington DC this weekend for the world's largest geography convention.

"Everybody's getting an extra nine to 12 days in Washington," said stranded traveler Rob Kitchin.

They've spent the past few days talking about places, they just can't get anywhere.

"For now, I'm going to sleep on a friend's couch and hope that the friendship lasts," said passenger Mary Gilmartin.

Hundreds of runners in Europe never made it to Boston for the city's marathon.

For stuck passengers, SeaWorld is offering free admission to three of its parks.

Experts say they don't expect a wind shift for at least the next three or four days, so travel plans remain up in the air.

Airlines say they're losing $200 million a day from the canceled flights.

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