The central monument is a long ramped path of grey concrete, cut into the lawn so that it reads, from above, as a gash opening toward the river. Argentine architect Alberto Varas won the 1998 international competition with this idea: not a triumphal arch, not a heroic statue, but a wound that will not close. Walking down it, you descend gradually below the level of the surrounding park, the city falling away behind you until there is only the water ahead. The path holds the names. They are inscribed on plaques of dark Patagonian porphyry stone, listed by year and then alphabetically, each one a person taken between 1969 and 1983. Where a victim was pregnant when she disappeared, the stone says so. Many of the panels are left blank, deliberately, waiting for the names not yet recovered.

Thirty thousand is the figure Argentines repeat, and the number matters because the regime worked so hard to make these people disappear without trace. But the park resists letting them dissolve back into a statistic. Each name on the wall was a student, a union organizer, a teacher, a doctor, a teenager, a parent. People were seized for expressing left-wing ideas, or simply for knowing someone who had. They were held in secret detention centres, tortured, and murdered, their bodies hidden so completely that for decades their families had no grave to visit. That absence is the cruelty the monument answers. By carving every recoverable name into stone and setting it beside the river, the park gives the disappeared the one thing their killers denied them: a place where they are named, and where they can be mourned in the open.

Eighteen sculptures stand among the lawns, twelve chosen by competition and six commissioned from artists known for their human-rights work. Roberto Aizenberg, Clorindo Testa, and the American conceptual artist Jenny Holzer all contributed works here. The park's most quietly devastating piece stands not on the grass but out in the water itself: Claudia Fontes' figure of a boy in mirror-polished steel, set some forty metres offshore, his back turned to the shore so no visitor can ever meet his eyes. He is a reconstructed portrait of Pablo Míguez, disappeared at the age of fourteen, one of the children the river took. His reflective surface dissolves into the estuary behind him. Poland's Magdalena Abakanowicz contributed her hollow, headless Walking Figures nearby. The art does not shout. It asks the visitor to slow down, to stand at the water's edge, and to carry the weight of what the smooth surface of the Río de la Plata still hides.

The fight for this ground was itself part of the story. In 1997, students from the National School of Buenos Aires first proposed a riverside park to honour the disappeared, and the city approved construction in 1998. The Monument to the Victims of State Terrorism was inaugurated on 7 November 2007. It rose only because mothers, grandmothers, and survivors refused for thirty years to let the country move on quietly, demanding investigations, trials, and truth. The park is run by a public commission, and its meeting hall hosts exhibitions and education programs so that nueva memoria, new memory, keeps being made. Argentina chose not to bury this chapter. It built it a monument by the river and made remembering an act of citizenship.