Up until this weekend, the western reaches of the Seym River, a meandering waterway flowing west across the Kursk region into Ukraine, was spanned by three low, two-lane, concrete-and-asphalt bridges that served road traffic for the southern Russian territory.
As of August 20, however, those three bridges are now impassable, partially destroyed by a series of Ukrainian attacks that pose serious problems for Russian forces struggling to contain Ukraine's two-week-old expanding invasion of Russia.
The goal of the effort -- which has stunned Russia, surprised the West, and possibly rewritten the narrative of the entire war -- remains uncertain, although President Volodymyr Zelenskiy signaled that at least one of the aims is to create a buffer zone.
But it's an open question whether a border buffer zone will change the fact that, some 400 kilometers to the south, Russian forces are on the verge of capturing Pokrovsk, a Donbas city whose fall would imperil Ukrainian supply and logistics lines all along the front line across the Donbas.
Here's a look at where things stand 30 months into Europe's largest land war since World War II.
All Eyes On Kursk
The last time Ukraine pulled off an offensive maneuver that reset the battlefield, not to mentioning gobsmacking outside observers, came in late 2022: in the eastern part of the Kharkiv region, and further the south, on the west side of the Dnieper River, in the Kherson region.
Ukraine tried to pull off an even more ambitious counteroffensive last year, but that ground to a halt, resulting in major personnel and equipment losses and widespread disappointment.
The Kursk invasion has surprised observers, but it's unclear if it will reset the battlefield.
More than 1,000 troops, including some of Ukraine's most battle-hardened units, backed by tanks and heavy weaponry, were believed to have been involved in the initial foray on August 6, which quickly overran undermanned and underbuilt border defenses. The number of Ukrainian troops has reportedly grown by at least five times since.
Your browser doesn’t support HTML5
Zelenskiy Aide Says Ukraine Helping Civilians Amid Food Shortages In Kursk Region
According to Ukrainian and Russian officials, open-source intelligence, and analysts, Ukrainian troops have been spotted digging fortified defensive positions in several locations. That suggests the invasion's goal is not just to attack Russian positions and retreat back across the border but to hold territory as a chip for future negotiations.
"It's a calculated risk that they've taken; they knew what they were doing," said Pentti Forsstrom, a retired Finnish Army lieutenant colonel who is now a senior researcher at the National Defense University in Helsinki.
"People were thinking: 'This is the attritional phase of the war, nothing special will happen, the fighting goes on, but nothing changes, so this is a good time to do something,'" he said. "And the Ukrainians did it. They didn't wait. They took the initiative into their own hands, forcing Russia to respond."
The strikes on the Seym bridges, in Kursk's Glushkovo district, are also significant: The bridge that was apparently hit sometime over the weekend -- announced in a drone video issued by Ukraine's air force commander on August 18 -- was the third to have been rendered impassable in recent days.
Destroying the bridges hinders Russia's ability to move forces and mount an effective defense, an effort that to date has been shambolic -- though that might change as more experienced units arrive. It also increases the risk that some Russian forces could be encircled.
"The strikes on the bridge crossings…and the advance of Ukrainian defense forces' forward units to the western bank of the river suggest that the objective…is to take control of a portion of Kursk Oblast south of the Seym," according to the Center for Defense Strategies, a Kyiv think tank headed by a former Ukrainian defense minister.
Your browser doesn’t support HTML5
Ukrainian Forces Near Donetsk Hope For Tide To Turn After Kursk Incursion
Satellite imagery shows Russian troops have tried to erect a handful of temporary pontoon bridges across the Seym.
On August 18, in his first remarks outlining the objectives of the incursion, Zelenskiy said Ukrainian forces were seeking to destroy "as much Russian war potential as possible," as well as to create "a buffer zone on the aggressor's territory."
There was another goal, said Mykhaylo Podolyak, a top Zelenskiy adviser.
"The third task is, of course, to show the type of war that Ukraine is waging, compared with the type of war that Russia is waging," he said in an interview with Current Time. "Russia is destroying populated areas. Russia, in fact, is going to occupy and seize populated areas. Ukraine does not intend to seize populated areas. It does not intend to occupy this territory."
In a separate speech, Zelenskiy trumpeted Russia's flat-footed response as an illustration that Moscow's threats about major escalation were illusory.
"It is the time when the world is shedding its last and very naive illusions about Russia, illusions that have significantly hindered the defense of Ukraine," he said.
Western observers, meanwhile, have been surprised not only by the Ukrainian success but also by the ineffectual Russian reaction.
"Russia is still pulling together its reaction to this incursion," U.S. Army General Christopher Cavoli, NATO's top military commander, said on August 15 during a talk in New York. "There has been a fairly slow and scattered reaction to it. Part of that is because it's not exactly clear who is in charge."
A Ukrainian soldier patrols an area of Sudzha, Kursk region, Russia, on August 16.
Send In The Conscripts
The Ukrainian advance has sent tens of thousands of Kursk residents fleeing; at least 130,000, as of August 20. It is a flood of people that has stretched resources and nerves in the regional capital, also called Kursk.
For the Kremlin, there's another, bigger people problem looming: the role of conscripts being deployed against Ukrainian troops.
Under Russian law, all men between the ages of 18 and 40 are required to serve in the armed forces. The law also puts some limits on deploying conscripts to war zones, requiring a minimum of four months of service and specialized training, and including an outright prohibition on deployment outside of the country.
That means the war in Ukraine has been fought only with contract volunteers -- "kontraktniki" -- as well as recruited prison inmates.
That, in turn, has insulated the wider Russian population from the horrors of the Ukraine conflict, which has killed or wounded at least 350,000 Russian soldiers (and a comparable number of Ukrainians), according to Western estimates.
Russian President Vladimir Putin has said multiple times that conscripts would not be deployed to combat areas. But the Ukrainian invasion of Kursk is changing that calculus.
At least 22 Russian conscripts went missing in the Kursk region in the first week of Ukraine's invasion, according to the news outlet iStories.
In the northern region of Murmansk, mothers of conscripts who began service in early July have circulated petitions demanding their sons not be sent to the Kursk region.
Relatives of conscripts from the central region of Bashkortostan told the news organization Vyorstka that some of their brothers and sons who had been stationed in the Kursk region had gone missing and may have been captured.
"What right do they have to send conscripts there?" one woman, who asked to be identified only as Olga, told RFE/RL's Siberia Realities. Putin promised that only kontraktniki would fight, she said.
Ukrainian forces have also released videos and photographs purporting to show scores of Russian prisoners of war, and observers say more than 1,000 soldiers may have been captured during the Kursk incursion. If true, that would present the Kremlin with an even bigger headache.
Idite Lesom, an NGO that helps Russians being mobilized or conscripted, said it had fielded scores of calls from parents complaining their sons had gone missing or were set to be deployed to fight Ukrainian troops.
"Formally, they cannot all be sent to the combat zone, but their commanders are obviously much more concerned now that they will get a slap on the wrist if they do not promptly carry out the order" to deploy to Kursk, Grigory Sverdlin, the NGO's founder, told RFE/RL's Russian Service.
Oksana Deyeva, a woman from the Voronezh region whose son was drafted in 2023 and had served near the Kursk village of Korenevo, published a petition on the website Change.org, calling on Putin to order the withdrawal of any conscripts.
"A full-scale offensive is under way on our territory today. Save the lives of soldiers who are not prepared for military action. You promised parents that [conscripts] would not participate in military action!!!! We believe in you," the petition read.
Deyeva did not respond to multiple messages from RFE/RL seeking further comment.
Ukrainians stand in line waiting to be evacuated by train in Pokrovsk. Authorities have started ordering civilians to leave as Russian forces close in on the city.
Pokrovsk Has (Almost) Fallen
Ukraine's successes have eclipsed more dire news further south, along other parts of the 1,100-kilometer front line.
Russian commanders, who have more men, more weaponry, and more willingness to conduct infantry-wave assaults, are grinding down Ukrainian defenses in three locations along a 70-kilometer section of the front: Chasiv Yar, Toretsk, and Pokrovsk.
Pokrovsk, in particular, is under critical threat, according to analysts and open-source maps and intelligence. On August 20, Russian forces were reported within 11 kilometers of the city, which has a dwindling civilian population of around 50,000. Authorities have called on civilians to evacuate the city, as well as the neighboring town of Myrnohrad.
"If Pokrovsk still has two weeks, then Myrnohrad has only a few days left," Yuriy Tretyak, the head of the local military administration, told RFE/RL's Donbas Realities.
Now a garrison town with supply depots and trauma facilities, Pokrovsk sits astride a key highway -- known variously as the T-0504 or N23 -- that heads northeast toward Kostyantynivka, a city with a major railway junction. Russian forces were even closer to the highway, less than 7 kilometers, as of August 19, according to Deep State, an open-source mapping group with ties to Ukraine's military.
Russia's Defense Ministry on August 21 claimed it had captured Nyu-York, a town also often spelled New York, located to the east of Pokrovsk. Ukrainian officials did not immediately confirm the town's loss, which would put more pressure on the defense of Pokrovsk.
Russia's seizure of the highway would be a major rupture of Ukrainian supply lines and would put further pressure on Kostyantynivka, which is being threatened from the northeast by Russian advances into the city of Chasiv Yar.
As of August 20, Russian forces controlled Chasiv Yar's Kanal district on the eastern side and have started sending scout units to try to establish a foothold across the Siverskiy Donets, the Donbas Canal, which Ukraine has relied on for defense.
The relentless Russian advances have again highlighted one of Ukraine's biggest problems: manpower.
Despite passing a new mobilization law this spring, the system for recruiting, equipping, training, and deploying new recruits continues to work slowly, experts said, giving Russia the advantage, overwhelming Ukrainian positions with bloody but effective infantry assaults.
"It's not about materiel, weapons. I have the feeling that Western aid is adequate enough. But the Ukrainians don't have the personnel to use those materials, to fire those weapons," Forsstrom told RFE/RL. "The Russians have the same problems in recruiting, but of course Russians have the money to attract soldiers. The Ukrainians don't. So they have to rely on the morale of the Ukrainian people."