We are learning more about how Ukraine managed to fend off repeated Russian attempts to advance on Kyiv in the early days of course of the war.

This takes us to a town near the capital that was really key in keeping Russian forces at bay.

Outgoing fire from a frozen foxhole, not far from the flaming pieces of an exploding

armored vehicle, as the quiet still of a nighttime bunker is shattered by what the soldier

says was a direct hit right nearby. This is what happened in the tiny town of Moschun, just northwest of Ukraine's capital city.

It was here, as much as anywhere else, that the Battle of Kiev was won. By early March,

Russian forces had flooded south of Ukraine's seat of power in its sights. They'd arrived just west of Washington, occupying that entire area.

The Yerpine River, the only thing between them and the town where Ukraine would make it stand.

Is it strange to just walk through this area now, you know, when it's safe?

He says what's strange was being here when all hell broke loose.

Three Ukrainian soldiers who fought here took us around Mushoon.

Before the ground assault, they said relentless artillery rained down.

There was little like a do with it.

Thinking they'd soften the town, the Russians decided it was time to strike.

With this bridge destroyed, they built a pontoon bridge here

and started sending special forces troops across the river.

Across the river, the Ukrainians waiting, some seen here, ready to fight back.

Street battles raged, homes were shredded, houses now with so many bullet holes like

freckles on a face.

The Russians, some seen here, actually took part of the town.

But that success would be short-lived because the woods were up next.

Moschun is surrounded by dense pine forest, the perfect area for Ukraine to stop and advance.

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