The conflict in Ukraine, which broke out exactly one year ago today (February 24), has claimed thousands of lives, driven millions from their homes, left entire cities in ruins, and stoked worries that it could escalate into an all-out war between Russia and Nato.

Here is a look at some of the conflict's major incidents.

Russia’s Invasion of Ukraine 2022-2023: One Year Later

2022

February 24

Ukraine is invaded by Russia from the north, east, and south.

The borders of Kyiv are rapidly reached by Russian forces, but they encounter fierce resistance in their attempts to take over the nation's capital and other northeastern cities. Volodymyr Zelensky, the president of Ukraine, records a video outside his office to demonstrate that he is still present and in authority.

March 16

Russia strikes a theatre in the strategic port city of Mariupol, where civilians had been sheltering, killing hundreds of people in one of the war’s deadliest attacks.

April 9

Hundreds of dead civilians are found in mass graves or left in the streets of Bucha after the Russian withdrawal from Kyiv, many showing indications of torture. Pictures shared online prompt world leaders to call for Russia to be held accountable for potential war crimes.

On this day, 52 civilians are killed and more than 100 are injured when Russian missiles strike a train station in the eastern city of Kramatorsk.

April 13

The Russian Black Sea Fleet's flagship, the missile cruiser Moskva, is damaged by Ukrainian missiles and sinks the day after, eroding pride in Russia.

May 16

During a nearly three-month siege, Ukrainian defenders of Mariupol’s massive Azovstal steel factory, the last Ukrainian stronghold, agree to submit to Russian forces.

May 18

Finland and Sweden submit their bids to join Nato, marking a key hit to Moscow.

June 30

Snake Island, which is off the Black Sea town of Odesa and was taken in the first days of the invasion, is reclaimed by Russian troops.

Ukraine is receiving more weapons from the West, notably HIMARS multiple rocket launchers supplied by the US.

July 22

With the help of Turkey and the UN, Russia and Ukraine reach an agreement to release grain supplies that have become blocked in Ukraine's Black Sea ports, putting an end to a standoff that threatened world food security.

August 9

Powerful explosions strike an air base in Crimea and the Russian government accuses Ukraine of being responsible for the vehicle bomb explosion that killed the daughter of Russian nationalist ideologist Alexander Dugin south of Moscow.

September 21

Putin orders the call-up of 300,000 reserve soldiers, a controversial decision that forces hundreds of thousands of Russian men to emigrate to surrounding nations to avoid being drafted.

September 30

Putin signs documents to annex four regions of Ukraine at a Kremlin ceremony.

November 9

In response to a Ukrainian counteroffensive, Russia declares its withdrawal from Kherson, the sole regional hub it had managed to seize. This is a humiliating retreat for the Russian government.

December 21

Zelensky visits the United States on his first trip abroad since the war began, meeting with President Joe Biden to secure Patriot air-defense missile systems and other weapons, and addressing Congress.

2023

January 1

A Ukrainian missile attack on the city of Makiivka results in the deaths of numerous recently recruited Russian soldiers. While Ukrainian officials estimate that hundreds of people have died, the Russian Defense Ministry claims that 89 servicemen have perished.

January 14

A Russian missile destroys an apartment building in the city of Dnipro, killing 45 people, as part of yet another round of attacks by Russia on the energy infrastructure of Ukraine.

February 20

In a meticulously planned high-risk security operation, Joe Biden visits Ukraine, demonstrating US support to Kyiv and hitting Russia with a heavy blow.