Denver-based Frontier Airlines on Tuesday announced the addition of 20 nonstop routes, including several international, in what company officials are calling “one of our largest international expansions ever.”

The introductory fares are sure to raise some eyebrows: As of Dec. 11, travelers can fly from Denver International Airport to Belize for $99.

That flight is the only new route out of DIA. At Frontier’s Orlando, Fla., hub, where new routes can be taken to Antiqua and Barbuda; Liberia, Costa Rica; and Turks and Caicos.

“Today’s announcement marks one of our largest international expansions ever and we are thrilled to now offer our customers affordable service to four more popular destinations offering both sun and fun,” Daniel Shurz, senior vice president of commercial, said in a statement.

Promotional fares must be purchased by Monday.