This is the spectacular installation at the Tower of London, commemorating 100 years since Armastice Day. There are 10,000 flames, which represent not just the soldiers who lost their lives, but all those who were bereaved or affected by the war. Each flame is ceremonially lit, creating a circle of light around the tower as a powerful symbol of remembrance. The lighting takes 4–50 minutes and the flames remain lit for around four hours. I really recommend you see this post from a previous commemoration.