With the Russian positions less than a kilometre away, we are at the very front of the Ukrainian resistance.
The soldiers of Sarmat Battalion are dug in below ground, holding one tiny part of this long line.
The front in this war stretches more than 300 miles down the east of the country.
The lines, and the trenches which mark them, were drawn years ago.
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Since the 2014 Russian invasion and annexation of Crimea, this has been contested land between Russian-backed separatists and Ukraine.
We are near the village of Pisky, just to the northwest of the Russian-held city of Donetsk.
The village is one of so many which dot along this front. Beyond it, are the trenches and beyond them, the Russian line.
The artillery is regular and close. “A few hundred metres away,” a soldier says as the latest round fall. He seems unfazed.
The platoon commander of this unit has been fighting in the region since 2014.
Lieutenant Denys Gordeev was not long out of law school when his focus turned to defending his country.
The new Russian invasion and this new eastern offensive have only hardened his resolve.
“I know why I am here. It’s my life, my children’s life, my kids, my wife and my Ukrainian people,” he tells me.
“I am Ukrainian. I can’t lose my country now. The enemy wants to destroy it, my county. Not only cities, not just killing people, but to destroy my nation.”
“That’s why your morale seems so high?” I ask.
“Yes,” he replies.
He shows us the anti-tank missiles supplied by the British.
“Yes, it’s a really good weapon for me,” he says, adding they need more urgently.
I ask if there has been a change in the tempo of the attacks at his position since the Russians announced the beginning of the new offensive.
“Not yet but it’s only been a day,” he replies.
“Only day one. What we have tomorrow, we don’t know but every night we feel more bomb attacks, more rocket attacks.”
Our conversation is interrupted by a much louder explosion.
“Now we must go in,” he says, his voice marginally more urgent.
The next 20 minutes are spent in the cramped living quarters. It is like a film set from World War One but the continued thuds outside remind us it is not.
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The Russians have regrouped on the land beyond us. All their forces are now concentrated in this part of the country.
But this new offensive will not be quick. The assessment here is that these are just preliminary strikes for a much larger assault in the weeks ahead.
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Some of the soldiers have been here, fighting and sleeping, for the last year.
There are more thuds outside. “Again and again and again. Whole time,” Denys says.
They are tired and short of weapons, but, on their own land and up against an invader, they believe they will win.