Even the Ukrainians could hardly believe what they found in Hlyboke.
"The Russians built up this bulwark," says Maksym Sintchenko.
"And then they just left without a fight."
Sintchenko, who goes by the nom de guerre "Graf," is the commander of the 247th Battalion of the Territorial Defense Forces, a branch of the Ukrainian military made up of reservists and volunteers.
On an overcast September afternoon, he's taking a closer look at the position that the Russian troops left behind in the village of Hlyboke.
The 44-year-old, a man with dark hair and a cheerful countenance, is walking through a former animal feed warehouse that was shut down long before the war.
The occupiers turned this concrete skeleton into a post when they invaded the Kharkiv region in northeastern Ukraine in late February.
The terms "position" or "quarters" don't quite do justice to what the Russians set up here.
It looks more like an improvised base, with Russian army engineers performing no small feat.
Not Far from Russia
A small wooden staircase leads down to the sleeping quarters, which have been dug into the ground.
Sandbags have been piled up as protection and the position is surrounded by the olive-green ammunition crates that can be found everywhere here, all of them emblazoned with a stamp reading: "Defense Ministry of Russia."
A few meters further on is an improvised chin-up bar, a bench for weightlifting and what appears to be the remains of an outdoor shower.
The occupiers, it is clear, made themselves right at home.
Hlyboke is just seven kilometers from the border.
Indeed, Russia is visible from the edge of the village, out across the reservoir and the sunflower fields.
At the beginning of the Russian invasion, the occupiers only briefly paused here and in the surrounding villages.
Their primary goal was Kharkiv some 30 kilometers further to the south, the capital of the eponymously named oblast.
But they ran up against the city's stubborn defenders, and after bitter and bloody fighting, the Ukrainians finally managed to drive the invaders away from the city in early May.
But Hlyboke and other villages near the Russian border remained in the hands of the invaders.
And for several months, units of Vladimir Putin's military were accommodated here, members of the 200th and 25th brigades, auxiliary troops from the pro-Moscow pseudo states in the Donbas and fighters from Chechnya.
They rotated every two months, says Maksym Sintchenko, but most recently only Russian troops were stationed here and no fighters from the self-proclaimed "people's republics" in the Donbas.
On Sept. 11, say Ukrainian soldiers, the Russians simply pulled out of Hlyboke.
Just a few days before, the Ukrainian army had surprised the Russians with a lightning offensive to the east and southeast of Kharkiv, driving the enemy troops out of Balakliya, Izyum and other strategically important towns in the region.
It is unclear, though, why the Russians elected to abandon Hlyboke and other villages north of Kharkiv.
Sintchenko believes they may have been anticipating a robust Ukrainian advance in this region as well.
In contrast to Balakliya or Izyum, the Russians left behind hardly any heavy equipment in Hlyboke.
But the fortified positions they abandoned, to which the DER SPIEGEL team were the first journalists to gain access, are quite impressive.
At the outskirts of the village, the Russians dug deep, wide trenches, complete with hollows for tanks.
The shelters carved into the earth are secured with thick tree trunks and the bunks inside apparently constructed with care.
The troops had even set up electric heaters for the approaching winter.
Indeed, Sintchenko is willing to admit that the Russians are superior to the Ukrainians in two areas: "In electronic warfare and in military engineering."
The Russians also set up shop on the grounds of a nearby weather station.
The vast complex with its bunker-like subterranean corridors and rooms could have - along with other facilities in the town - offered the occupiers adequate protection for quite some time, particularly given that the Russian border was just a few kilometers away.
Instead, they pulled out, apparently in a hurry.
Socks and underwear were still hanging from a clothesline, and the Ukrainians also found bags of bread in a pile along with green rations packets with "Russian Army" printed on them.
Putin's troops also left behind Orthodox prayer headbands and propaganda flyers.
A good two dozen posters of half-naked women are hanging above the beds in one of the rooms, while another poster shows a collage including a fully outfitted elite soldier in front of a large, white "Z," the symbol of the Russian invasion .
As Maksym Sintchenko and his troops inspect the facility, the booming of artillery can be heard in the background.
Pillars of smoke rise above the fields.
A white Lada with suitcases tied to the roof makes its way across a dirt track through a field: Some of the last civilians who had stayed in the area are fleeing.
The foremost frontline now runs through a neighboring village, says Sintchenko.
Two hours ago, he adds, four civilians were killed by artillery.
Men like the 44-year-old Sintchenko played an important role in the defense of Kharkiv, professional soldiers who command units of the Territorial Defense Forces, a kind of popular militia.
After 25 years in the army, Sintchenko took a training position last November at the military academy in the city.
But then came the Russian invasion on Feb. 24, and three days later, he joined the Territorial Defense Forces.
Just two hours after joining, he was already fighting in the north of Saltivka, a part of Kharkiv that has been hit particularly hard by the war.
On his 12th day of service, he was charged with assembling the 127th brigade of the Territorial Defense Forces.
He turned to friends active in the city's business community and also published two videos on social media calling for volunteers.
Some 80,000 people responded, and today, the battalion numbers 700 fighters.
The return to Kharkiv leads Sintchenko through the suburbs that he and his soldiers fought for in months past: Lypzi, Tyshky, Zyrkuny, a drive through a sea of rubble.
The commander says the next task is already awaiting his battalion.
He has been assigned with establishing defensive lines so that Putin's troops cannot march into Kharkiv once again.
