Millions of South Koreans were already en route to their hometowns Tuesday ahead of the Chuseok holiday period, with about 39 million expected to travel to different parts of the country for annual reunions with relatives.

On Chuseok, the country's traditional autumn harvest festival which falls on Thursday this year, families usually hold memorial services for their ancestors and eat traditional foods.

Airports, train stations and express bus terminals across the country were already packed early Tuesday, a day before the start of the three-day holiday.

According to the Korea Meteorological Administration, traffic congestion will worsen because of rain, which is expected to continue nationwide until Sunday.

The Korea Highway Corp. said 294,000 cars left the capital area Monday and an additional 327,000 are expected to depart Tuesday.

A company official said Seoul-bound traffic will be less heavy due to the long weekend but outbound traffic is expected to peak Wednesday, the first day of the Chuseok holiday.

They added that officials expected drives from Seoul to Busan to take more than ten hours on Wednesday.