The anti-Yanukovych revolt was called the "EuroMaidan revolution", as huge crowds demanded a pact with the EU.
Pro-EU President Petro Poroshenko will address the nation, after setbacks for the military in the eastern conflict.
Pro-Russian rebels pushed his army back from the key town of Debaltseve two days ago.
Later there will be a concert on the Maidan, including poetry, a choir singing the national anthem, and a performance of Mozart`s Requiem by the National Symphony Orchestra of Ukraine.
Mr Yanukovych - a political ally of Moscow - fled into exile in late February 2014, but soon resurfaced in the southern Russian city of Rostov-on-Don.
He said he had been ousted in an "illegal coup" and lambasted the "fascists" who had taken power in Kiev.
For weeks in the bitterly cold winter of 2013-2014 the Maidan was a vast campsite populated by the EuroMaidan protesters, who kept police at bay with barricades and burning tyres.
Most of those killed in the Maidan clashes were shot by snipers, and some uniformed police were filmed firing at protesters.
A ceasefire for war-torn eastern Ukraine, signed in Minsk on 12 February, looks fragile as shelling continues in some areas. An intense rebel bombardment forced some 2,500 government troops to retreat from Debaltseve on Wednesday, and dozens of others surrendered.
The village of Chernukhino, near Debaltseve, is now in rebel hands too, the Kiev-appointed governor of Luhansk region, Gennadiy Moskal, said on Friday.
The Ukrainian government, Western leaders and Nato say there is clear evidence that Russia is helping the rebels with heavy weapons and soldiers. Independent experts echo that accusation. Moscow denies it, insisting that any Russians serving with the rebels are "volunteers".