In keeping with the eco-friendly travel focus of our April issue of Global Traveler, “green” tourism opportunities and environmentally conscious vacation options pop up all over the world.

Even the cruising industry makes waves in the sustainable travel trade. Exhibit: the ferry-cruiser, Viking Grace. Based in the Baltic Åland Islands, Viking Line joined the ranks of innovative cruise ships as the world’s first passenger vessel utilizing wind power. Now equipped with a high-tech rotor sail, a cylindrical device propels the ship by spinning and harnessing wind power.

The ecological improvements come after the vessel was already known to be a sustainable ship — it has been fueled with low-emission liquefied natural gas since 2013. Now with the all-new rotor sail, Viking Grace hopes to reduce CO2 emissions by 900 tons yearly. The wind-powered cylinder is difficult to miss, stretching nearly 80 feet tall, 13-feet wide and passing through the water with ease. Developed by the Finnish firm Norsepower Oy Ltd., the simple, effective and primitive concept is revolutionary in the cruising industry and lightens the company’s carbon footprint.

This may be the first of its kind, but it won’t be the last. Two similar rotor sails, doubling the power output, will be installed on the line’s newest ship. While currently under construction in China, the new ship is expected to be fully operational by 2020.