Viking Ocean Cruises - This cruise lasts for 245 days and takes passengers to six continents and 59 countries.
Oceania Cruises - This cruise lasts for 180 days and takes passengers to 44 countries and 100 ports.
Silversea Cruises - This cruise lasts for 150 days and takes passengers to 34 countries and 54 ports.
Crystal Cruises - This cruise lasts for 139 days and takes passengers to 48 ports in 27 countries.
Seabourn - This cruise lasts for 146 days and takes passengers to 60 ports in 32 countries.
Grand World Voyage by Holland America Line - This cruise lasts for 128 days and takes passengers to 45 ports in 25 countries.
Regent Seven Seas Cruises - This cruise lasts for 117 days and takes passengers to 56 ports in 30 countries.
Cunard Line - This cruise lasts for 113 days and takes passengers to 42 ports in 27 countries.
Princess Cruises - This cruise lasts for 111 days and takes passengers to 41 ports in 26 countries.