The Russell Hotel in Sydney's historic district, The Rocks, has one room that is in high demand.

It's so popular that tourists are booking it up to a year in advance.

Charmion Lumsden, who works at hotel's front desk, said she received frequent requests from "all different booking agencies, always with notes, room 25, room 25".

The reason the room is popular, Japanese tourist Miyuki Kitayama told SBS, is because it featured in the Japanese anime series 'Free! Eternal Summer'.

"They use this hotel in the animation and actually it's [the] same as this hotel," Ms Kitiyama said.

Producers of the hugely popular show came to Australia in 2014 and used the hotel as the backdrop for a major episode, the main character's first trip overseas.



He stayed in room 25.



The show inspired Miyuki to visit Australia who said she even knows people who had flown to the country for just one day for the opportunity to stay in the room.

"Some people trip to here, straight after the broadcast."





Charmion Lunsden said she did not expect that the series would propel such an interest in the hotel.

"The amount of people that want to come and stay and see the hotel, we have Japanese tourists also just walking off the street to take photos of reception."



Ms Kitayama was not able to stay in room 25 this time, but staff allowed her a sneak peak of the room once it was vacated.



"For now, I can come in the room and take photos of this room," Ms Kitayama said.

"Actually, I am really happy today."







