You’ve got 72 hours - well, less than that at this point - to book a flight for $35 one-way on Southwest Airlines.

The airline is launching its annual (or is it semi-annual?) sale where the fares are based on the number of miles in your flight.

For travel of 450 miles or less, one-way fares are $35. For travel 451 to 1,000 miles, one-way fares are $65. For travel 1,001 to 1,500 miles, one-way fares are $95. And for travel 1,501 or more miles, one-way fares are $125.

For example, from Baltimore, $35 will take you to Boston, Detroit, Hartford, Newark and Pittsburgh. A $65 fare will get you to Charleston, Indianapolis, Little Rock or Orlando. For $95, you can hit Austin, Dallas or Omaha. And if you have the big bucks, $125 will get you to Albuquerque, Las Vegas, Los Angeles, Phoenix or San Diego. That's just to name a few. Check out the full list of fares and cities here.

Sound like a deal? Well, it is! And for all you AirTran fans, there's a companion sale with the same fare prices and mileage categories.

The fares are available for travel Nov. 30 to Dec. 14 and Jan. 4-Feb. 15. Fares do not include taxes and fees. Book by 11:59 p.m. Thursday.