A new five-star hotel on Jeju Island is under fire for saying its sauna windows were mirror coated when they weren’t.

Naked guests in the shower booths and bathrooms in the sauna on the second floor could be seen from the first floor at Grand Josun Jeju, which opened last month in Seogwipo.

According to a complaint posted on a portal site Tuesday, a man who stayed at the hotel on his honeymoon said his wife had used the sauna several times because she was told the windows were mirror coated.

The couple found out the windows were transparent only on the last day of their two-night stay, when they were strolling around the hotel.

The hotel, run by Shinsegae Group affiliate Josun Hotels & Resorts, apologized on its website later Tuesday, saying it had closed the sauna and was redressing the problem.

“You could even see the writing on the thermometer inside the sauna,” the wife wrote.

“The hotel said you can’t see anything from the outside during the day because the windows are mirror coated, and that they roll the blinds down in the evening.”

When the couple initially complained to the hotel staff, they were told that the blinds had been rolled up “by mistake.”

The interior of the shower rooms and bathrooms in the sauna could be seen clearly from the hotel entrance, the promenade, the parking lot and guest room balconies, he wrote.

“We paid over 800,000 won ($722.57) per night, and my wife and I used the toilets and took showers while people were watching,” the husband wrote, adding that they were in therapy due to the shocking experience.

He said the hotel had refused to put up a public notice disclosing that the sauna windows were see-through, had not apologized until the end of the Lunar New Year’s holidays, and had even called the police when guests complained.

This is not the first time a five-star hotel in South Korea has had a privacy issue.

When Park Hyatt Busan opened in 2013, the interior of the guest rooms could be seen from apartments across the street.

By Kim So-hyun (sophie@heraldcorp.com)