Alexander and Maria were crowned at the Assumption Cathedral in the Kremlin in Moscow on 27 May 1883. Just before the coronation, a major conspiracy had been uncovered, which cast a pall over the celebration. Nevertheless, over 8000 guests attended the splendid ceremony. Because of the many threats against Maria and Alexander III, the head of the security police, General Cherevin, shortly after the coronation urged the Tsar and his family to relocate to Gatchina Palace, a more secure location 50 kilometres outside St. Petersburg. The huge palace had 900 rooms and was built by Catherine the Great. The Romanovs heeded the advice. Maria and Alexander III lived at Gatchina for 13 years, and it was here that their five surviving children grew up. Under heavy guard, Alexander III and Maria made periodic trips from Gatchina to the capital to take part in official events.