Yet here in Hong Kong, which since its handover from the United Kingdom in 1997 has operated autonomously with its own laws and basic rights, such as freedom of speech and assembly, annual commemorations are held to mark the demonstrations. This city is the only place on Chinese soil where the June 4 Museum can exist.

Read: The death of democracy in Hong Kong

Not everyone here wants it to exist, though. Civil liberties have gradually been curtailed in Hong Kong, and the museum has not been spared, facing sustained harassment and suppression, a response reminiscent of the 1989 crackdown. This should come as no surprise. When a government’s worst behaviors officially never happened, the state has little reason not to behave in such a way again.

The June 4 Museum occupies half of the 10th floor of a cramped building in the Mong Kok neighborhood. The only sign for it is a small decal with a 64 logo in the building’s first-floor lobby. When the museum reopened in April of this year, it was met with a street protest by those loyal to the Beijing government. Someone put saltwater in the space’s electrical sockets to cut its power. The fire department showed up saying they’d gotten a call that the place was on fire. It wasn’t. But the crew’s presence briefly disrupted operations.

Kennis Tang, who serves as a museum guide, was not surprised by those events. The same thing happened in 2014, when the previous incarnation of the museum opened in a different part of Hong Kong. It had to close when the owners of the building were pressured by other tenants into declaring the museum’s space not zoned for exhibitions. It moved into and out of a series of temporary locations before the museum’s backer, the pro-democracy Hong Kong Alliance, bought the current space.

For several years after Hong Kong’s transfer back to China, Beijing made good on a promise to not interfere with Hong Kong’s way of life until the city’s full integration with China, in 2047. Hong Kong was an economic powerhouse, and mainland China, while growing fast, was wary of meddling. Little by little, as the balance shifted, that began to change. Antony Dapiran writes in City of Protest that from this reduction in relative economic power “emerged a deeper pride among Hong Kongers, based on the rule of law, civil liberties, rights and freedoms and clean and accountable government.”

In 2014, Beijing-backed changes to Hong Kong’s election process triggered months of Occupy-style protests that included as many as 100,000 people braving tear gas and pepper spray, in what became known as the Umbrella Movement. Despite the global recognition the movement received, the new restrictive electoral laws were still put in place and several of the protest leaders were jailed. There have been other signs of an erosion of freedoms as well. In 2015, Chinese state-security agents abducted five employees of a publishing house that printed and sold books critical of Beijing and detained them on the mainland; last year, a Financial Times journalist, Victor Mallet, was denied a renewal of his work visa here and then refused entry into the city after he interviewed an activist who supports independence from China; and right now, legislators are considering a highly controversial law that would allow the extradition to the mainland of individuals wanted for crimes there.