The summer solstice fires, also known as Sacred Heart of Jesus fires, are a custom that is still practised today in Tirol, particularly in the Tannheimer Tal Valley and the village of Kartitsch in East Tirol. They commemorate Tirol's resistance against Napoleon's troops in 1796, when the defence of the region against the approaching army was entrusted to the ‘Sacred Heart of Jesus’. As a result of the ‘Sacred Heart of Jesus Vow’ the Tirolean troops received a large influx of volunteers and was surprisingly able to repel the French advance. At the same time, the mountain fires also served as communication signals visible from afar to summon the troops for battle. In fact, the original significance of the fires can be traced back even further to the pre-Christian midsummer and St John's fires.