Or delayed. Many airports, including Gatwick, are already full, however some flights that were previously headed to London were able to land at other UK airports.
Tens of thousands of travelers have been left stranded overseas as dozens of planes have been rerouted to Amsterdam, Frankfurt, Lyon, and other European locations.
Air India has now canceled all of its flights to London after some aircraft were even forced to turn around and land in New York, Los Angeles, Mumbai, and Delhi.
The airlines that have seen the most cancellations and diversions include American Airlines, Virgin Atlantic, United Airlines, Air Canada, Delta, and British Airways.
Since the Icelandic volcanic ash cloud grounded and rerouted planes in April and May 2010, it has caused the worst interruption to UK aviation,
