ESTONIA. May 20, 2025. Conscript posing for portrait after finished exercise. Operation Hedgehog 2025 a large-scale international military exercise led by the Estonian Defence Forces. One of the largest military exercises in Estonia's history, involving over 16,000 troops from various NATO allies. The exercise focuses on training key tasks of Estonian and regional defense plans, enhancing interoperability between allied units, and testing rapid deployment and combat readiness.