What's better than seven days on a cruise? How about two weeks?

Carnival Cruise Lines recently announced that it will offer a series of 10- and 14-day voyages on six different cruise ships in 2015-16.

The expanded voyages, which will depart from seven different U.S. homeports, will provide passengers extended calls at popular destinations in the Caribbean, Bermuda, Mexican Riviera and The Bahamas.

Carnival will also be able to make its debut in Trinidad & Tobago as a result.

"Based on feedback from our guests and travel agent partners, we're delighted to offer these longer length voyages which provide vacationers an opportunity to visit some of the world's most breathtaking destinations while enjoying all the wonderful on-board innovations and features found aboard Carnival's ships," said Carnival's senior vice president of iteneray planning and revenue development Terry Thornton in a statement.

Reservations for nearly a dozen of the extended voyages opened on Friday.

The earliest longer length voyage available is the 13-day Mexican Riviera cruise aboard the Carnival Miracle, which is scheduled to depart from Long Beach, California on Jan 31. The journey will include a 2-day call in Cabo San Lucas and an overnight call in Puerto Vallarta.

In addition to previously announced extended trips onboard the Carnival Triumph and the Carnival Pride in 2015-16, lengthened voyages will also be offered on the Carnival Dream, Carnival Glory and Carnival Sunshine.

However, the earliest available extended cruise on either of those three vessels is scheduled for October 2015.

Passengers will also have the option of combining some of the extended cruises into three-week-long Caribbean adventures at an added cost.