They hiked for hours and crossed a river to get around the border fence with Macedonia.
Even before Balkan countries closed their borders to refugees, the situation in the port city of Piraeus was dire.
Slovenia, Croatia, Macedonia and Serbia tightened up their border policies.
Children as young as 6 weeks old have been injured in clashes between desperate migrants and authorities, Doctors Without Borders says.
"We all know the emptiness inside when we lose something so valuable."
Since Balkan countries tightened their border restrictions, tens of thousands of people are stuck in Greece.