Louisville Zoo in Kentucky, US, has opened the fourth phase of its new Glacier Run exhibition to the public.

The new attraction, the Seal and Sea Lion Habitat, is part of the US$30m (£20m, €24m) Glacier Run, which will see the arrival of polar bears at the zoo in 2011.

Construction on the exhibit began in 2008 and is now home to 4 California sea lions and a harbor seal with more animals scheduled to arrive in the coming weeks and months.

The exhibit's tank holds 108,000 gallon of recycled salt water and zoo visitors can view daily training sessions from a 200-seat amphitheatre built around the pool.

Louisville mayor Jerry Abramson said: "Glacier Run is an investment that will provide a major boost to our community and region's quality of life and will be a tourism attraction for years to come."

Once complete, Glacier Run will tell the story of the polar bear and educate visitors about the most pressing environmental challenges that threaten its existence.

The exhibit will recreate the natural habitat of the tundra and will eventually include residents such as polar bears, Steller's sea eagles, reindeer and Arctic fox.

There will also be a themed "town centre" for guests to visit, including a schoolhouse and general store in addition to the newly opened amphitheatre.

The first four phases of Glacier Run have now opened. They include the expanded Australian Walkabout, the Calistoga Splash Park at Glacier Run, Alice S. Etscorn Tiger Tundra exhibit and Seal and Sea Lion Habitat.

Whittenberg Construction Company was the general contractor for the Sea Lion Exhibit, which was designed by architects Peckham Guyton, Albers and Viets (PGAV) and Arrasmith, Judd, Rapp, Chovan. Landscaping was done by Korfhage Landscaping and Design.