Over 1.5 years, Ukraine 🇺🇦 has slowly but consistently implemented its obstacle-based fortification strategy and now has a solid and complex fallback line grid for most of the country.
Let's look at the results achieved and draw some conclusions, with bonus reviews from the soldiers!
1/⬇️
2/🧵
Over almost 5 years of war, fortification strategies have evolved a lot, with Ukraine having been on the defensive for the most part of these years, evolving the most.
With technology itself evolving, fortifications had to mirror it. In the case of drones, camouflage and sturdiness are now key to avoiding detection in the first place and withstanding strong fire from the enemy.
Attack and defense strategies have also evolved: the Russians employ large amounts of firepower and small groups of infiltrators, while Ukraine counters with stronger positions, engineering obstacles, and frequent drone reconnaissance and strike missions.
3/🧵
All this led Ukraine, at the start of 2025, to develop their now preferred style of fortifications, based on engineering obstacles, very sturdy and small trenches, and tight drone control, partially mitigating their pressing manpower problem and significantly complicating Russia's go-to attack strategy (infiltrations).
4/🧵
In Southern Ukraine, in addition to the two 2023 "Zaluzhniy Lines," in red you can see the new lines built by Ukraine ever since.
A half ring for Zaporizhzhia, 3 north-south lines to defend against Russia's Huljajpole offensive, a ring around Novomykolaivka and Pokrovske.
In between and in front of all this lie dozens of small barbed wire or ditch lines that will significantly dampen Russian infiltration efforts.
Some of these lines still have to be completed and are missing one or two elements relative to the conventional doctrine, but they're all at a sufficient level of preparation to make a difference when making contact with large amounts of Russian infiltrators.
At the moment, the new pink line is at the very first stages of building.
5/🧵
Also note the building order of these lines that the Ukrainians adopted: when the Russians first broke through at Uspenivka, the line defending Zaporizhzhia's south and east flanks was built first as a worst-case scenario fallback line, and only then did they gradually move eastwards when possible.
This always gave the Ukrainians a fallback line in case any breakthrough were to happen.
6/🧵
The Dnipropetrovsk Oblast is definitely the region with the most upgrades.
Pavlohrad's ring was upgraded from 1 to 3 ditches; the Synelnykove line is in the process of doing the same; Vasylkivka now has a half ring; Shakhtarske was made into a fortress city by multiple rings, something I had hoped to see for a long time; Mezhova now has 3 or 4 fallback lines behind it, just like Dobropillia and all of the Kramatorsk-Slovyansk agglomeration. Even Barvinkove is currently being fortified.
And, again, dozens of smaller engineering obstacle lines in front and in between all these lines, where they're impossible to replicate due to the proximity of the frontline.
7/🧵
The Kharkiv area is characterized by a complex mix of old and new lines.
Behind the Oskil River lie a partially complete and a complete defensive line.
A strong line has been built on top of a previous one as a fallback from all the Velikyi Burluk salients.
Velikyi Burluk is now a crucial node of the new defensive line behind Vovchansk and Kupyansk and is itself enclosed by a ring.
Kharkiv's front is defended by a complex overlap of an old and up to two new lines, effectively forcing the Russians to the flanks, which are also covered by new lines.
Older lines further towards Sumy and Bohodukhiv have and are in the process of being reinforced.
8/🧵
In general, for the first time since late 2024, I feel like saying Ukraine's whole east is now adequately fortified according to modern standards.
Don't get me wrong: there is still a lot of work to do, there are still weak spots and passages that need to be covered, but work is currently being done in these regards at the moment.
New lines are and will continue to be built in many new places around Ukraine, and older ones will be slowly but surely upgraded.
9/🧵
The "review" of these lines from the soldiers I've talked to is overwhelmingly positive.
They significantly slow down Russian infiltrations and give enough time to Ukrainian drones to detect and strike them before they enter the greenery.
They also mitigate the manpower problem, as these lines are not made for infantry to hold constantly but for drones to observe and strike promptly.
10/🧵
I would also like to direct your attention to a practical case: Ivanivka, Novopavlivka direction, Dnipropetrovsk Oblast.
In October 2025 the Russians had finally reached one of Ukraine's obstacle lines for the first time north of Novokhatske and Zelenyi Hai and, with difficulties, were even able to cross it, the Vovcha River, and consolidate in Ivanivka itself but were eventually cleared out.
At the moment, the Russians still weren't able to regain lost positions in the settlement, and footage of Russian infantry eliminated while trying to cross this obstacle line is abundant, together with footage of Russians attempting to cross other smaller engineering obstacles all around Ukraine's frontlines.
This practically and objectively testifies to the utility of such lines, and I can only hope more and more will be built in the future, without forgetting about drone development, which is key to maintaining control over these engineering obstacles.
11/🧵
Summing everything up, I feel like the weakest areas are currently Ukraine's Chernihiv-Sumy borderlands due to the comparatively lower amount of fortification work having been done and due to the high amount of safe and covered infiltration routes available to possible Russian infiltrators.
The Dobropillia direction also doesn't have a high margin of error but is held by capable units, and the fortifications are also not bad.
The Stepnohirsk direction is also a bit weak in terms of fortifications, but natural obstacles, Zaporizhzhia's proximity as a logistical and accumulation hub, and Ukraine's "half-initiative" should compensate.
In the Prosyana direction, fortifications are also a bit weak, but they're in the process of being upgraded, and the terrain is complex for possible Russian advances.
Izyum's eastern flank, too, needs some upgrades, especially due to the big forest suitable for deep Russian infiltrations, but Ukrainian units are attempting to give the city some breathing room as of now.
12/🧵
Thanks for reading! Feel free to leave your feedback, questions, tips, criticisms, or whatever you'd like down here in the comments, and as always, remember to join my Discord: discord.gg/P3XsgQFBPV.
If you'd like to support my work with a donation instead: coff.ee/playfra
Or, even better, if you'd like to support the defenders of Kostyantynivka and make the difference in this battle:
• PrivatBank: privat24.ua/send/iz0y5
• Card number: 5168752151822858
• PayPal: l.knyazhytsky@gmail.com
• Wise: wise.com/pay/me/vratkos
• BuyMeACoffee: coff.ee/playfra
*The maps shown do not in any way break OPSEC or represent sensitive data. Everything that was mapped was done using public sources, and both sides know well about what is shown in these maps.
• • •
Missing some Tweet in this thread? You can try to
force a refresh
While the battle for #Kostyantynivka is in full swing, it's interesting to look more in-depth at the situation in 🇺🇦 Ukrainian-controlled Donbas and to understand what will come after this crucial battle, focusing on the next city in line for 🇷🇺 Russia: Druzhkivka.
After almost 9 months of battle for the city (and especially its flanks), Russian forces were finally able to exploit a Ukrainian weak spot in the southwestern part of the city, near Illinivka and Berestok, and with heavy losses, gained the possibility of consistent infiltrations into the now contested key southwestern high-rise district of the city.
On the eastern flank, instead, Russia is putting the accent on spreading between the dense residential buildings, and their infiltrators reach as deep as the Staryi Piter citadel and the KMZ plant in the center.
Meanwhile, the Russians, since early 2026, have been able to establish a solid kill zone for Ukrainian logistics attempting to enter or exit Kostyantynivka.
At the moment, solid planning and careful execution are required to even get to position, just like an assault or infiltration operation.
From the ground, the feeling is that this battle will end in late summer or autumn.
Because of this, the Russians are likely already eyeing Druzhkivka as their next target.
Just like Kostyantynivka, it's one of the 4 biggest cities of Ukrainian-controlled Donbas that also constitute a formidable urban defense belt.
Druzhkivka has just a bit fewer inhabitants than Kostyantynivka but is half its size: 33 km².
This city, too, sits on the Kryvyi Torets River valley but is divided into 3 parts because of the Kazenyi Torets River.
It also has a sizable high-rise and industrial area.
Let's look at some defensive strong and weak spots.
1/🧵
🇺🇦🇷🇺 A bit more than a year passed after Ukraine made a risky bet on a new and modern type of fortification, that is, a series of engineering obstacles, and it is interesting to summarize and analyze from different perspectives what was accomplished in this time.
2/🧵
- From a strategy point of view, a major switch from trench building to obstacle digging happened. Up to 2024 Ukraine prioritized building lines of defenses that were characterized by large trench systems; now the actual "defensive line" is the ditches and barbed wire and tripwire in front of them, which significantly aid the FPV kill zone.
Small but sturdy trench systems are built just behind those obstacles.
3/🧵
- Regarding trenches specifically, the preferred digging method is now the following: Dig a ~2 meter deep trench on the side of a treeline, then cover it with a metal frame, sturdy roofing, and packed dirt on top of it. Very small holes covered by anti-drone metal frames are left in case it's necessary to engage in a fire battle.
This way, Russian FPVs are forced to brute-force a very small opening on the top part of the trench by consistently hitting it with precision, thus really compromising only one section of the trench system.
Some systems are even equipped with fire extinguishers and backup building materials to attempt field repairs of the trench.
Airstrikes and artillery strikes have a larger, but not catastrophic, effect on them: looking at real examples, a number of systems built even in early 2025 still more or less have their roofing intact.
🧵The defense of Fortress Orikhiv 🇺🇦: everything you need to know about the city's future.
Analyzing natural obstacles and topography, fortifications, weak and strong spots, logistics, and urbanistics.
1/🧵
2/🧵
Orikhiv is a town in southeastern Ukraine with 14,000 pre-war inhabitants that covers about 10 km² (about 1/4 of Pokrovsk and 1/7 of Bakhmut).
This city has been no more than 7 km from the contact line since 2022 and has seen constant fighting ever since.
3/🧵
Together with Kamyanske, Huljajpole, and Velyka Novosilka, Orikhiv is part of the town line where the Ukrainians were able to stop the Russian advance in the first days of the war.
That same year it stood against a Russian encirclement attempt.
Then, it served as the main logistical, accumulation, and command hub of the Ukrainian 2023 southern counteroffensive, and after its failure, it continued to serve those purposes, significantly holding back Russian attempts to reactivate the Zaporizhzhia direction.
🧵 Southeastern front: Ukrainian 🇺🇦 and Russian 🇷🇺 forces continue clashing and fighting for the initiative, while Ukrainian engineers exploit this time to significantly enhance their fortifications.
🧵Thread 🧵1/⬇️
2/🧵
In this thread, I will focus on:
- Describing the tactical-strategical situation in all directions of the southeastern front
- Describing the progress with Ukrainian fortifications
- Commenting on my opinions about each situation and giving my point of view on the general situation.
Stepnohirsk direction. In general, the situation remains stable and without significant changes.
In Prymorske and Stepnohirsk, Russian forces continue to infiltrate all over the settlements but are struck and often destroyed by tight control of Ukrainian FPVs.
Ukrainian forces continue to be present in both villages and sometimes conduct physical clearings.
Just east, Russians infiltrate along the indicated route to the solar farm and then attempt to reach Lukianivske, but they're struck by FPVs along the way, and the few who sometimes end up in the settlement are immediately cleared.
In my opinion, the main Russian objectives in this direction (photo #4) are:
- Getting as close as possible to Zaporizhzhia for it to eventually be in drone and artillery range.
- Pushing Ukrainian forces behind the Konka River.
- Pushing towards Orikhiv from the west, consolidating well their positions on the dominant heights, and placing drone teams there to critically endanger Ukrainian supplies into Orikhiv.
Photos #2 and #3 show the situation with the fortifications and topographic overlays.
Some personal considerations about the Ukrainian 🇺🇦 "counteroffensive" in the Oleksandrivka direction.
2/🧵
1. First of all, I disagree with figures citing massive Ukrainian gains of up to 400 (!) km².
According to my information, the total recaptured territory by the Ukrainians is around 20 km², and it is all concentrated at the Russian bridgehead over the Haichur River in the Ternuvate direction, which was almost completely liquidated except for Pryluky.
Here, a methodical clearing was conducted (not always without losses and with good organization and coordination), positions were taken and consolidated, and Russian forces do not have anymore the possibility to infiltrate like they did some weeks ago at all.
3/🧵
The bulk of the territory that goes in the incorrect 400 km² count is south of Verbove, in the Oleksandrivka direction. Here, first of all, the Ukrainians cleared remainders of old Russian infiltration attempts into Novooleksandrivka, Oleksiivka, and treelines south (the Russians never consolidated those positions, and the Russians had long given up on attempts to capture these settlements, almost totally focusing on Huljajpole: t.me/PlayfraOSINT/3…).
After weeks of tedious mapping of every single trench, foxhole, emplacement, ditch, blockpost, dragon's teeth, and barbed wire line, I've finally finished the Berdyansk sector, one of the most heavily fortified pieces of territory in the whole of Ukraine.
The total count is as follows:
- 40,000 trenches, foxholes, emplacements, firing positions
- 450 separate anti-tank ditches
- 600 separate dragon's teeth lines
- 220 separate barbed wire lines
Let's look at the most interesting things I found along the way.
3/🧵
The area of the Ukrainian 2023 Velyka Novosilka counteroffensive.
De-facto, Russia's line "0.5". It was designed to absorb the first blow of Ukraine's counteroffensive and soften the Ukrainians for the first line of defense.