The US-based owner said the newbuildings will add a new dimension to its river cruising options throughout the country.
It added the concept for the new boats will differ from the current paddle-wheelers and coastal ships.
The vessels are an addition to the Victorian-style riverboats which ACL is currently building at its preferred Chesapeake yard in Salisbury.
It currently operates six ships throughout the United States, offering voyages from Maine to Florida, the Mississippi river, the Columbia and Snake rivers and Alaska.
