Most mainland tourists head to Hong Kong for the shops, but a few are venturing away from the malls to see something they won't find at home.
They are heading to a museum commemorating the emergence and subsequent suppression of the pro-democracy movement that swept the mainland 23 years ago.
The museum, organised by the Hong Kong Alliance in Support of Patriotic Democratic Movements in China, is in a 1,000 sq ft first-floor flat in Yu Chau Street, Sham Shui Po.
It remains the only institution in China commemorating the June 4 crackdown in Tiananmen Square.
One visitor was a Beijing student who gave her name as Selina. 'I think the truth should be made known,' she said. 'Many people outside Beijing don't know what happened.'
She was born in 1989 and was previously sceptical about the cause advocated by the students. Her parents told her the crackdown brought chaos to the capital, leaving them unable even to buy milk for her.
The visit to the June 4 Museum changed her opinion.
'Now I know the roles of [former premier] Li Peng and [late reformist leader] Hu Yaobang , and why the students were protesting ... it was a pity, there should not have been any violence,' she said.
The display outlines the events leading up to the crackdown and how it unfolded, as well as artefacts such as leaflets circulated by the students and black-and-white photographs of corpses and bullet cartridges.
There are also copies of Hong Kong newspapers and advertisements placed by professionals after the crackdown in 1989. One was from chief executive-elect Leung Chun-ying, who said he 'strongly reprimands the Chinese Communist authority for their bloody massacre of Chinese civilians'.
While Selina, an exchange student, visited the museum with a local friend, Mr and Mrs Zhang, from Guizhou province - who declined to reveal their full names - chose to visit during their holiday.
'We planned to shop in Hong Kong, but I read about this museum on the internet,' Mr Zhang, 27, said.
He said he knew there had been a 'student movement', but he had learned little about it at school.
After the visit, he said: '[The exhibition] is inspiring. It is an alternative view ... We need to think about it.'
Alliance chairman Lee Cheuk-yan said about 7,000 people had visited the museum since it opened in April, and about 1,400 were mainlanders.
'We have not done a lot of publicity, but many mainland tourists came to our museum after they saw posts on Weibo,' he said. 'It shows the topic arouses great interest on the mainland, and our museum can become a base for filling in the blanks, and filling up [forgotten] memories among the mainland Chinese.'
Also visiting were a group of 52 Form Three pupils from the Caritas Fanling Chan Chun Ha Secondary School. Their teachers said the visit was a good way to tell the children - born in the 1990s - what happened.
Sarah Tam, 17, watched a 10-minute video explaining the background to the crackdown. She said the displays had helped her understand.
'I thought June 4 was some revolution for social welfare in China,' Tam said. 'Now I realise it was a brutal and extreme suppression by the government. June 4 must be vindicated as soon as possible.'