Crystal Cruises wins ten consecutive years of Travel + Leisure's Readers' Poll for World's Best Large-Ship Cruise Line. Unmatched Record of #1 Wins in the Cruise Industry. Its luxury ships, the 940-guest, 50,000-ton Crystal Harmony, Crystal Symphony and 1,080-guest, 68,000-ton Crystal Serenity are considered three of the most spacious and luxurious ships in the world. With itineraries of seven- to 101 days, the fleet cruises worldwide, including destinations in Asia, Europe, South America, the Caribbean, Alaska, New England/Canada and the Panama Canal. The difference is Crystal clear. marlboro ships worldwide