Russian (East Slavic) chronicles speak of a monk, Lazar the Serb, newly arrived from Serbia, inventing and building a clock on a tower in the Grand Prince's palace in Moscow behind the Cathedral of the Annunciation at the request of Vasily I, in 1404. It was the first ever mechanical clock in Russia, and also the country's first public clock. It was among the first ten such advanced clocks in Europe, and was regarded as a technical miracle at the time.