As late as the eighteenth century, an arc of monasteries formed Moscow's outer line of defence against invaders. The southeast was historically the direction from which the Tartars came and thus most strongly defended. While the Novospasskiy and Simonov relied on the strength of their ramparts and bastions to hold flat terrain beside the Moskva River that was the final obstacle to sacking Zamoskvareche, the steep east bank of the Yauza River lent a natural advantage to the smaller
Andronikov Monastery (Spaso-Andronikov monastyr; Mon, Tues & Thurs– Sun 11am–6pm; closed Wed and the last Fri of each month; $3). Founded in 1360 by Metropolitan Alexei, who vowed that, should he survive the stormy return sea journey from Constantinople, he would found a monastery and dedicate it to the saint whose feast day coincided with his safe return to Moscow – which turned out to be Our Saviour (Spas) – it got its present name after he was summoned to Crimea to treat the Khan's ailing wife and entrusted it to the monk Andronik, who became its first abbot. Its most famous monk was the great icon painter
Andrei Rublev.
After the October Revolution the monastery was turned into a prison camp, then into housing for workers at the nearby Hammer and Sickle Factory, and finally scheduled for demolition – but reprieved by the postwar upsurge of patriotism. In 1960 it was formally reopened as the Andrei Rublev Museum of Early Russian Art, in honour of the 600th anniversary of his birth. Though still designated as a museum, several of the buildings are once more occupied by Orthodox monks and institutions, including a choristers' school (you might hear them practising).