BUCHAREST, Romania (AP) — Tens of thousands of people turned out in Romania’s capital on Friday to watch a military parade that included troops from NATO allies to mark the country’s national day.

The annual parade at the Arc de Triomphe in Bucharest brought together thousands of marching soldiers as dozens of combat jets and helicopters flew overhead. Many spectators waved Romanian tricolor flags: red, yellow, and blue.

Friday’s ceremony celebrated the 105th anniversary of Great Union Day of 1918 when modern-day Romania was formed after its unification with the neighboring regions of Transylvania, Bessarabia and Bukovina. After communism ended in 1989, Dec. 1 was declared a national holiday to commemorate the ethnic Romanians in Alba Iulia who declared a union of Transylvania with Romania.

In a reception held at Cotroceni Palace after the parade, Romania’s President Klaus Iohannis described the day as a holiday “that brings Romanians together, no matter where we are, reconnecting us to the spirit of our national unity.”

“We remember the culture and traditions that define us,” he said. “And, above all, the great crossroads of our history, when only through solidarity and unity were we able to resolutely overcome difficulties that seemed insurmountable.”

The U.S. Department of State offered its congratulations Friday, saying Romania’s “leadership within the NATO Alliance strengthens our collective security, especially in the Black Sea region,” and said future cooperation between the two nations “grows ever brighter.”

Since Russia invaded Ukraine, Romania has played an increasingly prominent role in the alliance — which it joined in 2004 — including hosting a NATO meeting of foreign ministers in November 2022. In December, Romania inaugurated an international training hub for F-16 jet pilots from NATO countries and other partners, including war-torn Ukraine.