Nearly 34,000 Jews were killed within two days in 1941 at a ravine near Kyiv when the city was under Nazi occupation.
Ukraine has marked the 80th anniversary of the Babi Yar massacre, one of the most infamous mass slaughters of the Holocaust.
Nearly 34,000 Jews were killed within two days in 1941 at the wooded Babi Yar ravine in the Ukrainian capital, Kyiv.
The massacre was carried out by SS troops and local collaborators when the city was under Nazi occupation during World War II.
Ukrainian President Volodymyr Zelenskyy laid flowers at the monument to the victims on Wednesday.
"Babi Yar, two short words that sound like two short gunshots, but carry long and horrid memories for several generations," Zelenskyy said in a statement.
"Because they know and remember that not two gunshots sounded in Babi Yar, but hundreds, thousands, tens of thousands times more."
Zelenskyy is Ukraine's first ethnically Jewish president, and most of his grandfather's family was killed during the war.
All Ukrainian schools on Wednesday held a lesson dedicated to the 80th anniversary of the tragedy.
The Ukrainian Foreign Ministry has described this date as "sad and deeply symbolic in the history" of the country.
"According to various estimates, the Nazis in Babi Yar executed between 100,000 and 200,000 people," Zelenskyy added.
"Aside from Jews, those were Ukrainians and Roma, prisoners of war and patients of a psychiatric hospital ... Someone will hear these two scary words and these scary numbers for the first time."
Ukraine has started the construction of a Babi Yar memorial complex and a museum at the site of the mass executions and plans to unveil it in 2025-2026.
Last week, the Ukrainian parliament also passed a law defining anti-Semitism and establishing punishments for anti-Jewish hate speech.