(CNN) -- Huge billboards stating, "We love having you here" greet you every few miles, so it's impossible not to feel welcomed on the island of Jeju.
A special autonomous region of South Korea, Jeju is well known among Koreans and is considered one of the country's top vacation and honeymoon destinations. Now the tourist gurus on the island want the rest of the world to know about it.
Jeju already has recognition from UNESCO. Nine sites on the island were designated geological attractions or "geoparks" last month. Three years ago, UNESCO named three heritage sites here.
CNN visited Sunrise Peak, holder of both titles, and the most popular tourist attraction in Jeju, created some two million years ago by volcanic eruptions.
It is a grueling hour-long trek to the top, not grueling because of physical exertion, but because of the thousands of school children and tourists squeezing along the same narrow path.
Jeon Yongmun is a geologist and has made the trip more than 100 times. He checks for weather and tourist erosion on the site. Pointing to a rock standing two meters tall, he says, "This rock is a very unique shape but the rock position is unstable and some day later this is ready to collapse."
The grassy crater is visible at the top from a safe distance, but Jeon warns it's too dangerous to walk on it as it is full of snakes. And in the 1950s, he tells me it was also home to a solitary horse -- a Jeju resident had led the horse all the way to the top to graze and then couldn't be bothered to take it back down again.
From 2.2 million visitors in 2006, Sunrise Peak is expected to attract 3.8 million this year. Jeju's provincial government says the number of foreign tourists has jumped 108 percent in just four years.
Another World Heritage site is the Manjang Caves, a series of caverns created by lava tubes from the volcano 200,000 years ago.
"The lava columns and the scale is very big and very wide. In Hawaii, the lava tubes are small and not well preserved in the micro-structure," says Jeon.
The temperature drops ten degrees during the walk into the caves. On the way Jeon checks the temperature and the carbon dioxide levels and finds that humidity is at 90 percent.
Jeju is becoming increasingly popular with Chinese tourists and now authorities are going one step further and encouraging direct Chinese investment.
Luxury housing projects are springing up all over the island. Malaysian developers Berjaya are building a $3.6 billion resort complete with a hotel, shopping center and casino.
Berjaya project director Tang Vui Woon says, "At the moment we can see an influx of tourists from China and Japan. So we are definitely targeting the Chinese market."
A new neighborhood and golf course that is being built nearby has already struck a successful note with Chinese investors. Of the 220 holiday homes already sold, half of them are now Chinese owned.
A few government sweeteners certainly help. Any foreigner who buys a condominium costing over $500,000 is automatically given a long-stay visa. After five years, you can claim permanent residency.
An hour and a half flight from Shanghai, two and a half hours from Japan, Jeju's government is in the middle of an aggressive advertising campaign, promoting Jeju as the island of choice for business or pleasure.