The Yonhap News Agency reports that in the first quarter of this year alone, a record high 1.11 million holidaymakers from South Korea visited Vietnam, up 24.1 percent from the previous year, surpassing the 1-million mark in a quarter for the first time.

Last year, more than 3.4 million South Koreans visited Vietnam for a 44 percent year-on-year increase, accounting for more than one fourth of total international arrivals to the country (15.5 million), according to the Vietnam National Administration of Tourism.

"Vietnam remains one of the most favorite destinations for South Koreans. Famous tourist spots such as Ha Long Bay, Hanoi, Da Nang and Hoi An are heavily favored, particularly middle-aged tourists," said Park Jong Sun, head of representative office of the Korea Tourism Board (KTO) in Vietnam.

An unusual factor in growing interest in each other’s country has been the phenomenal success the Vietnamese men’s football team has achieved under their South Korean coach Park Hang-seo.

A 15-day visa waiver for South Korean tourists to Vietnam and an increase in the frequency of direct flights connecting major cities in both countries have also contributed to making Vietnam a leading choice for South Korean tourists.

South Korean airlines Asiana and Jeju Air are offering daily flights between Busan and Da Nang, increasing the route’s capacity by 86 per cent. The central city became the top foreign destination for South Koreans last summer, according to Korean e-commerce website Ticket Monster.

Last December, Jeju Air began operating flights everyday between Daegu City and Da Nang. The Daegu-Da Nang flight takes around five hours.

Korean Air, the oldest and largest air carrier in Asia, also launched a direct air route between Busan and Da Nang last year.

South Korea is the biggest foreign investor in Vietnam, with its electronics giant Samsung making up almost 25 percent of Vietnam's exports last year which was $245 billion.

South Korean investors have registered projects worth over $65 billion in the country, Park said.

"Samsung has opened several enormous factories that manufacture phones and electronics. Hanoi and Ho Chi Minh City both have little Koreas where a significant number of South Korean expats live," said Mark Gwyther, founder of MGT Management Consulting, a tourism consultancy firm in HCM, told the South China Morning Post.

While Vietnam is the midst of a tourism boom with a record high of 15.5 million foreign arrivals in 2018, a year-on-year rise of 20 percent, the numbers remained lower than that of neighboring countries in the region.

Thailand (38 million), Malaysia (25 million), Singapore (18.5 million) and Indonesia (15.8 million) received more tourists than Vietnam

Deputy Prime Minister Vuong Dinh Hue told the National Assembly last year that the country needs to stop relying on crude oil and focus on tourism to sustain economic growth.

"It is better to get one million tourists than try to find one million tons of crude oil because tourism is more eco-friendly and safe for the economy," Hue said.

Many Vietnamese tourism agencies claim the country should relax its visa policies and simplify procedures to attract high spending tourists from Japan, North America, Northern Europe, China and South Korea. The current 15-day visa exemption should be extended to 30 days, they say.