WANDO, South Korea—If there's such a thing as a mecca for seaweed lovers, it's in South Korea.

At the recent international seaweed expo in the small fishing town of Wando in southwestern Korea there was plenty of the slimy stuff to eat, spread on one's body or even use as a fuel for cars.

One of the biggest draws was a kiosk for sea mustard-infused green ice cream, topped with extra helpings of dried kelp.

Sea mustard, a type of seaweed, isn't just there for the taste. "Unlike other ice creams that normally start to melt in 15 minutes, this one lasts for almost an hour," explained vendor Kim Sung-hee. "The secret is an edible ingredient that can't be disclosed plus sea mustard."

On the opening day, more than 2,000 people were treated to miyeokguk, a brown-seaweed soup. Organizers said it was designed to mark the year 2014, in which Wando played host to the world's 'first' algae expo.