The Baltic states are moving to bolster NATO’s eastern flank by testing a prototype defensive line in Latvia, part of a wider effort to protect the region’s borders with Russia and Belarus. Latvia, Lithuania and Estonia, all of whom are NATO and European Union members, agreed in 2024 to build the Baltic Defense Line, a network of fortifications designed to slow or deter a possible military attack. The prototype is being built and tested at the Sēlija military training range in southern Latvia, Latvian state television reported. Latvian soldiers are working with the US Michigan National Guard and the Danish armed forces during exercises. Around 200 soldiers, mainly military engineers and sappers, are taking part in this phase of the training until June 11. The Baltic Defense Line is expected to link with Poland’s East Shield program, a defense and deterrence project that aims to strengthen security along 800 kilometers of the country’s northern and eastern borders by 2028. Testing defenses The prototype defenses in Latvia are a small section of what the future Baltic Defense Line could look like. It includes trenches, armored positions, bunkers and concrete anti-tank obstacles known as “dragon’s teeth”. “We have a unique opportunity to practice things here before we start building anything on the Baltic defense line,” National Guard Captain Roberts Zariņš told Latvian Television. “Because on the Baltic defense line, everything has to be perfect – there is neither time nor money to tinker with it on the spot.” Soldiers said the prototype site would help them identify the strengths and weaknesses of different layouts.