The spiritual capital of Russia, home of the Trinity Lavra of St Sergius, the country's foremost monastery with its golden domes. A town of pilgrims and tourists 70 km north-east of Moscow, with a deep history of Orthodoxy.
The Trinity Lavra of St Sergius is the magnet for everyone who comes to Sergiyev Posad, and frankly it is the reason to make the trip. The town is small, but the Lavra complex is so powerful that pretending there is much else to the visit would be disingenuous — though there is enough around it to fill the time.
The main thing is the ensemble of the Trinity Lavra of St Sergius, a UNESCO site and a working monastery for men, founded by St Sergius of Radonezh in the 14th century. A lavra is the highest rank of Orthodox monastery, and there are only a handful in the Russian tradition. Inside is a concentration of architecture from many periods on a compact site:
Allow 2–3 hours to see the Lavra itself at a calm pace, more if you want to visit the museums or stand through a service. Entry to the grounds is free; individual museums and displays are charged.
If time remains, the town has a Toy Museum (Sergiyev Posad is the historic centre of matryoshka nesting-doll and wooden-toy making) and the Blinnaya Gora viewpoint opposite the Lavra, from which the postcard view of the whole ensemble opens up. Do not miss this angle: from below, the scale does not read.
The honest answer is that Sergiyev Posad can be done in one day from Moscow. Arrive in the morning, walk the Lavra, have lunch, take in the views, and go back. Staying overnight makes sense if you want to catch an early service without the crowds, or to combine the trip with other Golden Ring towns — the classic tourist circuit of medieval towns north-east of Moscow; Pereslavl-Zalessky, Rostov and Yaroslavl lie further along the same road.
The town is 70 km to the north-east, and there are two main ways to reach it:
By car, take the Yaroslavskoye highway; on weekend mornings the exit from Moscow is reliably jammed, so allow extra time.
Everything of interest is compact and walkable. From the station to the Lavra is the only route you really need, and it is short. Public transport is practically unnecessary for sightseeing. The road from the station goes uphill, which is worth bearing in mind if you have limited mobility.
Weekdays overall are noticeably freer than weekends — the crowds of tour coaches come on Saturdays and Sundays.
The town feels inexpensive relative to Moscow. A subject of its own is the monastery baking and kvass: honey cakes, pies and honey mead are sold right by the Lavra, serving as both a snack and a souvenir. (Kvass is a lightly fermented drink made from rye bread, barely alcoholic.) You can have a full lunch in the refectories and cafés nearby — look for places a little away from the main entrance, as right by the gates there is a premium for the view.
Saving is easy: snack on the baked goods instead of a restaurant meal, and at the Lavra itself pay only for the museums that genuinely interest you.