Yaroslavl has none of Suzdal's hush and none of Moscow's weight. It is a working Volga city of about 577,000 people, bigger than Kostroma (267,000), and its old center is a tight zone of about 110 hectares that UNESCO listed in 2005. Legend says Prince Yaroslav the Wise founded it around 1010 after killing a bear, which is why a bear is on the city flag. The date that matters more is spring 1612, when Minin and Pozharsky's militia gathered here before marching on Moscow and Yaroslavl served for months as the country's de facto capital.
The honest part for a winter visit comes early. The frescoed 17th-century churches that made Yaroslavl famous are closed to protect the paintings: Elijah the Prophet from 22 October to 1 May, the monastery cathedral, the belfry platform and the Epiphany church from 1 October to 1 May. You still get the exteriors, the museum halls, the Volga under ice and almost no tourists. If the frescoes are the whole point, come between May and October. Three days is right because two cover the center and the south bank, and the third goes to Rostov Veliky, the one Golden Ring town that fits a day.
Day one is the monastery and the old center, day two the embankment, the Strelka and Korovniki, day three Rostov on its lake. Start on a Wednesday: the combined museum ticket is sold only Wednesday to Sunday, and most halls and the art museum close on Mondays. The Russia page has the basics, 5 Days in Moscow covers the capital you'll pass through, and 3 Days in Suzdal is the ring's other arm.