BARCELONA, Spain (AP) — Dozens of boats carrying activists and aid for Palestinians in Gaza set sail from the northeastern Spanish city of Barcelona on Wednesday.

Organizers of the Global Sumud Flotilla say that more than 70 boats and 1,000 people from around the world will participate, with campaigners saying it’s the biggest civilian-led mobilization of its kind against Israel’s actions in the Palestinian territory.

Nearly 40 boats were leaving Barcelona while the rest will join the fleet from other ports along the Mediterranean as they sail eastward, according to Thiago Ávila, one of the flotilla’s leaders who spoke at a news conference in Barcelona on Sunday during a symbolic send-off event. Bad weather had forced organizers to delay their departure, which was originally planned for April 12.

As attention has turned to the Iran war, activists hope that their latest mission will revive attention to the plight of Palestinians living in Gaza.