‘Our god is a strong castle’ – this line from Martin Luther's hymn adorns the tower of Wittenberg’s Castle Church. The place of worship was constructed in 1506 on the foundations of the Elector of Saxony’s former castle. In 1517 Martin Luther is said to have nailed his 95 Theses to the door of this very church, though the scene was likely fabricated afterwards to emphasise this huge moment in history. Both Luther and his fellow reformer, Philip Melanchthon, have their final resting place inside the church. The Castle Church has been a UNESCO World Heritage Site since 1997. A worship service takes place every Sunday at 10 a.m.