If you're trying to get to the Ravens football game against the Indianapolis Colts this weekend, you might have a hard time unless you're planning a road trip.

Flights are already sold out on many airlines that fly to Indianapolis from Baltimore-Washington International Thurgood Marshall Airport. As for train travel, Amtrak has seats available but the trip would take you about 19 hours one way.

Demand for airline tickets has been so fierce that AirTran said Monday that it will add an extra flight Saturday at 11:30 a.m. to Indianapolis from BWI that will get passengers there in time for the Saturday night game. The airline also added a flight returning Sunday at 8 a.m.

But you have to act fast to get that flight - the additional Boeing 737 can ferry only 137 passengers to Indianapolis.

"We are happy to answer the high demand for flights to Indianapolis this weekend," AirTran spokesman Christopher White said.

AirTran recently tapped into Ravens fever by unveiling a plane with the Ravens mascot on the tail. The football team's corporate suite holders and sponsors will fly to Indianapolis this weekend aboard that plane, White said.

All Southwest Airlines flights to Indianapolis are booked for the weekend, and the airline doesn't plan to add additional flights, said spokesman Paul Flaningan.

That leaves the open road.

If you don't want to go it alone, Wnst.net - short for We Never Stop Talking Baltimore Sports - is taking a charter bus full of fans to the game. Tickets range from $475 to $575, and include the bus ride, hotel, tailgate party and an upper-level game ticket, according to the company's Web site.

Baltimore Sun reporter Michelle Deal-Zimmerman contributed to this article.