There are now more than half a million refugees from Ukraine in neighboring countries, the UN said on Monday, with people heading desperately west to central Europe after the invasion of the Russia last week.

Here is an overview of the situation at the borders of Ukraine:

Poland: More than 100,000 people crossed from Ukraine into Poland on Monday, according to Polish border guards, the highest figure received by Ukraine’s European neighbors since the start of the invasion.

Since February 24, border authorities have allowed at least 377,400 people to enter its border crossing points with Ukraine, according to a tweet on Tuesday.

The longest line is at the Medyka crossing point, said border guard spokeswoman Anna Michalska.

On the Ukrainian side of this border, a 20 kilometer (12 mile) line of vehicles stretches through neighboring villages. Residents told CNN that the number of people moving towards the border has decreased over the past day.

The first days of the evacuations were chaotic, with many people walking great distances to the border in cold conditions, they said. But now many volunteers from local villages have set up temporary shelter and donated food.

A CNN team at the border spoke to many non-Ukrainian citizens who say authorities still give preferential treatment to Ukrainians crossing the border.

CNN also encountered Ukrainian nationals who were waiting in line in their cars, but who decided to abandon their vehicle and walk to the border because they thought it would be faster.

Many men escort their families to the border, knowing they are likely to be turned away and unable to leave. Ukraine has banned men of military age from leaving the country as it seeks to bolster its armed forces.

Slovakia: Waiting times at Ukraine’s borders with Slovakia extend up to 35 hours at Ubla, to the northeast of Slovakia, and 12 hours at Vysne Nemecke, to the southeast. Another pass at Velke Slemence sees less congestion.

A total of 54,304 people had entered the country by Tuesday morning, according to the Slovak border police.

According to the agency’s spokesman, the guards have not knocked down a single person since the conflict began, which means that such incidents have occurred on the Ukrainian side. About 15,000 people passed through three crossings from Sunday morning to Monday morning, about a third of them non-Ukrainians, they said.

Romania: A total of 89,000 Ukrainian citizens have passed through the Romanian border since the Russian invasion, 50,000 of whom subsequently exited to other countries, according to official border records.

Traffic jams were noted at the border with Hungary, but police confirmed to CNN that crossings are less busy today and people are clearing them faster.