Until five years ago, Yeosu was an unremarkable, out-of-the-way city on the southern coast of South Korea. Despite a temperate climate, scenic islands and a spicy local cuisine, the city was, among tourists, virtually off the map. A largely rural municipality spread out over a peninsula and 317 islands, it has three commercial and residential hubs that used to be the only places to find anything resembling bustle.

Then fate smiled on the city. Yeosu (pronounced YUH-sue) was chosen to host the 2012 World Expo, the smallest city in a generation to have the honor.

Since then, this place of 300,000 residents has gone on a building binge. The sprawling Expo site, which stretches along the waterfront on the eastern edge of the city, has sprouted 22 new futuristic buildings and structures that would seem more suitable for fast-paced Seoul.

And large portions of Yeosu have undergone major infrastructure upgrades, including road improvements and new transport links, in part to accommodate the 10 million visitors the city initially expected to attend the Expo from the time it started, last month, through its end, Aug. 12.

"Yeosu has grown 20 years' worth in just a few years," said Moon Ha-Na, a representative for the Yeosu World Expo organizing committee, during a tour of the Expo site in March.

Its improvements are being explored by the more than 1 million visitors to the Expo who are taking in its ambitious environmental, cultural and educational exhibitions from 104 countries and 10 international organizations, including the United Nations.

A quick expansion

For South Korea's part, it has created a spectacular structure called the Big-O, which uses lights and lasers to project kaleidoscopic shows on a giant screen of water, and the Korea Pavilion, whose design suggests a huge silver wave. It also has installed a new aquarium, the largest in the country, that is spacious enough to comfortably house 200 animal species. And across the bay, the glittering, sail-shaped MVL Hotel -- a scaled-down imitation of Dubai's Burj Al Arab -- has a gleaming facade.

Still, the Expo may have exposed some growing pains. The influx of so many visitors in a small city with a new tourism infrastructure has caused a strain, especially when it comes to places to stay. While several hotels were built or renovated to accommodate tourists, there is still a shortage of available rooms. According to the Expo's tourism department, on an average day during the Expo in May, there was demand for more than 35,000 rooms, but Yeosu has only 9,941 rooms. The Expo organizing committee encourages visitors who can't find lodging to stay in neighboring towns. Alternative accommodations have also been opened in community centers, temples, churches and campgrounds.

The off-site lodgings may be just the push visitors need to explore the few sights around Yeosu that weren't created for the Expo. Ron Anderson and Corrie Hulse, two U.S. expatriates who teach English at the Yeosu campus of Chonnam National University, suggested a few nearby attractions -- such as Odongdo, a camellia-covered island connected to the mainland by a wide walkway. But, Anderson conceded, "There's nothing you can point your finger at and say 'This is what Yeosu is famous for.' Except the food."

Hulse, a self-professed food lover who has lived in Yeosu since 2007, agreed.

"Jeollanam-do, this province, is known for having the best food in Korea, so if you're a foodie, this is the place to come," she said.

After coffee, Hulse introduced us to boribap, which she described as make-your-own bibimbap, the signature Korean dish, at the restaurant Jin Bok.

An island with a view

After lunch, with lips still burning, my husband and I set out for Dolsan Island, the one excursion everyone recommended. The large, mostly rural island is connected to the mainland by Dolsan Bridge, a beautiful sight at night when it is aglow with soft neon lights. (A second bridge to the island was recently completed.) After a 40-minute bus ride through farmland along scenic oceanfront cliffs and past small strips of sandy beach, we arrived at the island's southern tip.

A steep uphill hike delivered us to Hyangiram, one of four Buddhist hermitages in Korea. There, amid temple buildings wedged into the rocky outcropping, we were treated to lovely, expansive views of the surrounding island-dotted sea.

Before returning to Yeosu proper, we stopped at a one-room museum in a seemingly derelict complex: the North Korean Semi-Submarine Exhibition Hall. On display inside was a largely intact, purportedly North Korean vessel that, according to the entertainingly propagandist information panels, was heroically sunk in 1998.

For dinner later that night, our last in Yeosu, we met up with Mina Park, a local public-school teacher and Yeosu native who lives in the city's Yeoseo-dong district.

"Ten years ago, it was all fields," she said of the area, now a vibrant nightlife district.

And the reputation of the city as a whole?

"Even a lot of Koreans don't know where Yeosu is," Park said with a laugh.

But now, with the Expo in full swing, that, too, is changing.