Ringed by barbed wire and high gray walls, and once the site of a secretive military detention center, the museum just south of Taipei makes for a surprising tourist hot spot.

The Jing-Mei White Terror Memorial Park, housed on the campus of a former military school, is a chilling reminder of the excesses of Taiwan’s not-so-distant authoritarian past when its rulers imposed martial law for four decades. The moldering concrete buildings with fading paint were once the site of secret tribunals where political dissidents were tried and the detention center where at one point several hundred people were held in crowded quarters.

Once known as the Jing-Mei Detention Center, the site has found new appeal in Taiwan after U.S. House Speaker Nancy Pelosi and pro-democracy activists who have criticized China met there in August, with visitor numbers rising in the weeks since. Its relevance was also underscored at the Chinese Communist Party’s twice-a-decade congress that took place last week, during which Beijing’s determination to absorb its democratic neighbor was a major talking point.