The queue of trucks starts more than 20 kilometres from Poland's eastern border.
Hundreds of Ukrainian lorries are parked along the road in an unbroken line, caught up in a trade dispute that's putting new strain on Polish-Ukrainian relations.
At Dorohusk and other key crossing points, where Ukrainian refugees once poured across to a warm welcome, Polish truck drivers now block the road with their cabs in both directions, choking the flow of traffic.
Humanitarian and military aid are waved through into Ukraine, as is perishable food and livestock.
Everything else gets stuck.
Ukraine's ambassador to Poland has called the hauliers' protest a "stab in the back" from a country that has been a close ally ever since Russia launched its full-scale invasion.
Ukrainian drivers have been sleeping in their cabs for over a week, waiting to cross, and are running out of supplies, money and patience.
On Friday, they said they were advancing towards the crossing at about a kilometre a day.
But Polish truckers manning the roadblock were equally frustrated and forthright.
They said they were forced into this extreme step to protect their livelihoods after the EU lifted all entry restrictions on Ukrainian carriers.
It did that soon after the war started.
"I think the EU wanted to help Ukraine, and that's fine. But it didn't really think through the fact that Ukraine would take over our markets," the chairman of the strike committee in Dorohusk, Pawel Ozygala, told the BBC.