Large strides were made in sustainable travel last month when Carnival Corporation began construction on its new line of cruise ships. The ships will be fully powered by liquefied natural gas — considered the world’s cleanest burning fossil fuel — in a new Green Cruising initiative. The ships will be the first of its kind to get 100 percent of its power from this source — an environmental breakthrough for air quality and cleaner emissions. They are the most environmentally friendly ships in the company’s history.

This is part of Carnival’s larger commitment to sustainability laid out on its recently developed sustainability website. Carnival is the world’s largest leisure travel company, and its environmental efforts impact larger industry trends. Lines like Costa Cruises, Crystal Cruises, Disney Cruises and others are also a part of a larger effort to shift to green cruising. These efforts include the implementation of solar power, recycling and a commitment to more transparency on the brands’ practices.

Cruising is still not the most eco-friendly form of travel, but with these recent strides companies continue to reduce their impact on the environment.