Paris officials have turned an urban problem into a public service: They’re selling the city’s “love locks” as souvenirs and donating the proceeds to refugee groups. The Guardian first reported the news back in December, and now—beginning on Saturday, May 13—the locks will be auctioned off online.

For traveling couples, the padlocks they affixed to the iron grills of the French city’s bridges, initials scrawled on the surface, were a symbol of romance. But to Parisian officials, they were a civil danger. Fearing that the locks would weaken overpasses like the Pont des Arts, the city began dismantling the metal trinkets in 2015.

Left with 1 million padlocks (which totaled 65 metric tons of scrap metal), authorities needed a creative way to repurpose the waste. So they decided to sell 10 metric tons of locks to members of the public, marketing them as relics of the city’s bygone history.

“Members of the public can buy five or 10 locks, or even clusters of them, all at an affordable price,” Bruno Julliard, first deputy mayor of Paris, said in a statement quoted by The Guardian in 2016. “All of the proceeds will be given to those who work in support and in solidarity of the refugees in Paris.”

The locks will be sold in a variety of lots, some of them just as a single souvenir, others in groups. Smaller lots are expected to sell for anywhere from $100 to $200, while pieces of the padlocked railings could go for as much as $5000 to $9000 apiece. Proceeds will benefit the Salvation Army, Emmaus Solidarity, and Solipam.