Luxury line Seabourn orders another new ship

Luxury line Seabourn has ordered another new ship for delivery in 2018.

The as-yet-unnamed, 604-passenger vessel will be a sister to a ship the line ordered earlier this year for delivery in late 2016, the line said today in an early morning announcement.

At 40,350 tons, the two vessels will be about 26% larger than the three Odyssey Class ships that Seabourn has rolled out since 2009, but they'll hold about 34% more passengers, based on double occupancy. As a result, they'll have about 6% less space per passenger.

While based on the Odyssey Class design, the new vessels will have one more deck than the earlier ships and expanded public areas.

The orders come as Seabourn is in the midst of transferring its three older vessels -- Seabourn Pride, Seabourn Spirit and Seabourn Legend -- to Windstar Cruises.

The line's three Odyssey Class ships -- Seabourn Odyssey, Seabourn Sojourn and Seabourn Quest -- made their debuts in 2009, 2010 and 2011, respectively. They each hold 450 passengers at double occupancy. For a glimpse of what the vessels in the series are like, click through the carousel below.