More than one million migrants and refugees reached Europe this year, including over 970,000 who made the dangerous journey across the Mediterranean, the UN refugee agency said Tuesday.
About half were Syrians fleeing the country's brutal civil war, according to the new figures released by the UNHCR and the International Organization for Migration.
"The number of people displaced by war and conflict is the highest seen in Western and Central Europe since the 1990s," the UNHCR said, referring to the conflicts in the former Yugoslavia that decade.
A total of 3,692 migrants died or disappeared crossing the Mediterranean sea this year, IOM said.
The figures were released as Turkey's state-run Anatolia news agency reported that 11 more people, including three children, drowned in the Aegean Sea, underscoring the grave risks taken by those striving to reach Europe.
Greece was by far the leading landing spot for migrants to Europe this year, with 821,008 arrivals, including 816,752 by sea.
At certain points over the last 12 months upwards of 5,000 people were landing in the Greek islands each day.
But the rate of arrivals in Greece has eased slightly since November, partly due to increased maritime patrols by Turkey and partly because of colder weather.
Overall, sea arrivals this year dwarfed those of 2014, when the UNHCR recorded 219,000 migrant landings in Europe via the Mediterranean.
The UN has previously said it sees no let up in the coming months and that the number of migrants who reach Europe in 2016 could exceed the 2015 figures, especially if relentless violence in Syria persists.
"We know Syrians will go on trying to reach Europe until there is a fundamental change in the factors that are pushing them to leave," UNHCR chief Antonio Guterres told the UN security council on Monday.
Guterres said there was need for a "New Deal" between the international community, especially Europe, and Syria's neighbours who have born the brunt of the refugee influx caused by the civil war.
Afghans made up 20 percent of migrant arrivals in Europe, while seven percent were Iraqis.
After Greece, Italy received the second highest number of migrants, with 150,317 people reaching its territory this year, all by sea.
This marked a slight decline from 2014, when 170,000 people landed in Italy after crossing the Mediterranean from North Africa.
Rounding out the list of European countries that saw migrant arrivals in 2015 was Bulgaria (29,959), Spain (3,845), Cyprus (269) and Malta (106).
"We know migration is inevitable, it's necessary and it's desirable," said IOM chief William Lacy Swing,
"But it's not enough to count the number of those arriving... We must also act," he added, calling for "legal, safe and secure" migration for those forced to leave their home country.
Reflecting on the last 12 months, the UNHCR criticised the "initial chaotic reaction" in parts of Europe to the flood of migrants, but applauded signs that a more coordinated response was now emerging.
But a unified EU positon remains elusive, with Hungary and Slovakia having made threats of legal action against the bloc's controversial plan to distribute 160,000 refugees across member states.