Cruise.com via ShermansTravel offers a Princess Cruises 5-night Mexico round-trip cruise for two, with prices starting from $696. That's the lowest price we could find by $402. Book this travel deal by June 15. Buy Now Tips It's the second offer on the landing page. This round-trip cruise aboard the Royal Princess departs on December 9 from Los Angeles, CA. Some restrictions may apply; fees, government taxes, and fuel supplements are additional.