Estonia’s defensive fortifications along the Russian border have evolved rapidly in recent years, moving from the construction of an ordinary border fence to a full-scale military defence line – infrastructure built to restrict enemy military mobility.
2022: border reinforcement and a shift in NATO doctrine
After Russia’s full-scale invasion of Ukraine and the migration crisis engineered by Belarus, Estonia rushed to finish work – delayed in previous years – on its barbed-wire fence and the installation of modern sensors. NATO’s Madrid Summit in June 2022 was the key political turning point, at which member states agreed a new strategy: moving from “react after an invasion” to active deterrence, meaning defence of allied territory from the very first metre. That laid the groundwork for planning physical military obstacles.
2023: developing the concept and cooperation
The Estonian Defence Forces and the Estonian Centre for Defence Investments (ECDI) began a detailed analysis of the terrain and the development of engineering solutions. Talks between the Baltic states intensified over creating a single, coordinated defence belt to prevent any possible “lightning war” by Russia.
2024: testing the bunkers
The Baltic Defence Line pact was concluded on 19 January 2024, when the defence ministers of the three Baltic states signed an agreement in Riga on establishing the Baltic Defence Line. Estonia announced plans to build around 600 bunkers, setting aside roughly €60 million. In spring 2024, meetings began with landowners and municipalities along the border. In summer, the first contracts were signed for building concrete bunker prototypes. Durability testing of the bunkers followed as early as September 2024, when the Defence Forces carried out live tests on three concrete bunker prototypes at Estonia’s central training range, checking their resistance to artillery strikes.
2025: bunker construction begins
Digging of anti-tank trenches began in summer 2025. Estonia started construction work in the south-eastern border area, the Setõmaa region, home to Estonia’s indigenous Seto people. The first experimental 500-metre stretch of anti-tank trench was built right up against the Russian border and gradually extended to 4 kilometres. By the end of the year, installation of bunkers on the first section had begun, along with the mass procurement and delivery of military materiel, including “dragon’s teeth”, to temporary storage sites near the border.
2026: pilot project completed, and an anti-drone network
The Setõmaa phase was completed in June this year, with the first stage of the pilot project successfully finished in the forests of south-eastern Estonia: the first 28 concrete bunkers built, and more than 10 kilometres of anti-tank trenches reinforced with timber.
Alongside the physical fortifications, Estonia’s Ministry of the Interior has begun building a nationwide anti-drone network, installing the first fixed drone detection and surveillance systems along the border between the Latvian border crossing and Luhamaa.
Over the coming years, Estonia plans to complete the remaining network of 600 bunkers and to build a total of 40 kilometres of anti-tank trenches, fully integrating them with natural forest and bog obstacles.
The situation in Setõmaa today
In the pine forests of Setõmaa, twenty-eight concrete bunkers and more than 10 kilometres of timber-reinforced anti-tank trenches have already been built. Estonia continues to weave the €60-million Baltic Defence Line into its border forests.
In the pine forests of south-eastern Estonia, 28 concrete bunkers and more than 10 kilometres of anti-tank trenches with timber-frame reinforcement have already been built. Right now, the forest tracts of Setõmaa serve both as construction sites and as natural obstacles for the Baltic Defence Line. As Lieutenant Colonel Ainars Afanasjevs, of the engineering inspectorate at the general staff of the Estonian Defence Forces, told public broadcaster ERR, two fortified strongpoints have already been set up in the country’s north-east and south-east.
As previously reported, the €60-million programme envisages deploying around 600 bunkers, thousands of pyramid-shaped concrete structures known as “dragon’s teeth”, and a belt of anti-personnel mines along the eastern border. More than 20,000 such obstacles have already been delivered, some of them moved to forward storage areas as close as possible to the defensive positions, A. Afanasjevs added.
One section of the defence line links a bunker to a trench with a specially treated pine timber frame, its walls reinforced with geotextile and steel mesh. The trench’s pitched timber roof is covered with a protective net designed to neutralise drone strikes. The forested terrain shaped the course of construction from the very outset. Because of the wooded and boggy ground, the first bunker-construction procurements exceeded the budget limits set by law, forcing officials to scale the first stage back to a trial project of just 28 bunkers.
The forest as a defensive element
Looking more broadly, all three Baltic states are using their existing forest tracts as a strategic line of defence. Along Lithuania’s border, for instance, the dense forest cover already makes much of the terrain unsuitable for armoured manoeuvres. The trilateral initiative also envisages planting tree avenues and deepening drainage ditches, turning them into natural obstacles that will complement the system of concrete bunkers and timber trenches.
The trenches built so far have also drawn criticism. Pēters Tali, a member of the National Defence Committee of the Rīgikogu, Estonia’s parliament, said they were too shallow and would only be effective once mined: “The most significant weak point is that Estonia has no anti-personnel mines.”
Estonia, following the example of its Baltic neighbours, has withdrawn from the Ottawa Convention banning anti-personnel mines. In peacetime, however, no explosives of any kind will be laid along the border. In Tali’s view, a genuinely secure defence belt requires both anti-tank and anti-personnel mines, as well as specialised engineering obstacles, not trenches alone.
The main purpose of the fortifications is to slow and constrain the movement of attacking forces, not to stop them outright, turning a stranded tank into an easy target. “No anti-tank trench on its own will stop a tank,” Afanasjevs explained. The Estonian Centre for Defence Investments plans to build around 40 kilometres of anti-tank trenches along the forested border. In Setõmaa, work will continue on building the remaining network of 600 bunkers.
The efforts of our northern neighbours are also pushing Latvia to work much harder to reinforce its own eastern border. Let us hope the new defence minister, a professional with an excellent grounding in military science, can see this work through in the shortest possible time.