La Coupole, located 5 km from Saint-Omer (Nord-Pas-de-Calais), is one of the most impressive remnants of the Second World War in Europe. It is a symbolic place of the Nazi oppression, due to its overwhelming mass, the nature of its underground facilities and the suffering of the slave labourers who built it.
https://www.lacoupole-france.co.uk/history-centre.html