Finland is preparing for a potential nuclear conflict with Russia, according to a report published by the British newspaper The Times.

The country has developed an extensive network of more than 5,000 dual-purpose shelters capable of accommodating nearly one million people.

During peacetime, these underground facilities operate as swimming pools, saunas, gyms and children’s play areas. They are also equipped with air-filtration systems, independent power supplies and water reserves.

Steel doors are designed to withstand blast waves, while the shelters are intended to provide protection against chemical, biological and nuclear threats.

The facilities are constructed with emergency use in mind but can later be leased for civilian purposes.

The Times also noted that Finland has a military reserve of 900,000 people and mandatory fortification infrastructure, making it one of NATO’s best-prepared members in terms of defense.

Russian officials, meanwhile, have repeatedly stated that Moscow has no intention of attacking NATO countries.