The Vernisage at Izmailovo is a large, outdoor shopping market, full of all sorts of Russian souvenirs, crafts and other interesting things to buy, along with paintings, "flea market" items, rugs from central Asia, and a few places to get a bite to eat or a drink. You can easily spend the better part of a day just wandering around among the stalls looking and buying. In the dead of winter, however, you will probably only be able to stand the cold for a couple of hours. Don't forget to try some of the shashlik (kebabs) with flat bread. Once you're inside the Vernisage market area, it's easy to find - just look for the smoke from the grills.
Inside the Vernisage @ Izmailovo
Adjacent to the Vernisage is the Kremlin at Izmailovo ("Kremlin" is the Russian word for "fortress" so there are many kremlins in Russia, in addition to the most famous one, which sits on Red Square). This Kremlin also has some stores, restaurants and museums, including the Museum of the History of Vodka. Near the market is Izmailovsky Park, which is a large, wooded park with walking trails.

There is also a very large, outdoor general merchandise market which surrounds the front entrance and the back (the largest part is in the back) of the Vernisage. That market can also be interesting if you have never visited a Russian outdoor market. There you can buy just about anything, from food and clothing to electronics and household goods. This is the sort of market where many Russians do their daily or weekend shopping.

The area is easily accessible by Metro. Travel east of the city center on the "dark blue" Metro line to the Partizanskaya station. Exit the station and follow the crowds, walking left out of the station for about 300 meters. You will walk past a large hotel complex on your left before you reach the market, and as you get close to the Vernisage, you will also walk through a small outdoor market area where vendors sell mostly clothing and snacks, before you reach the Vernisage entrance. The Vernisage requires a 10 ruble payment to enter. If you reach the area by car or other means, and are unsure which way to go, just look for the buildings that look like old Russian architecture, with onion domes and lots of wood. Clicking on the link above will take you to the website for the Vernisage, and you will see a picture there that shows you what it looks like and what to look for.  Most drivers know which area tourists want to go to, and will take you directly to the Vernisage entrance.

Saturdays and Sundays are the only days when the Vernisage is really much of an attraction. On weekdays, it is open, but only a fraction of the shops are open and selection is very limited. During the work-week, Wednesday is the best day to visit.  There are more craft vendors there on Wednesdays, although there are still only a fraction of the shops open, compared to weekends.  On weekends, all shops are open until about 5:00 pm, and many stay open longer, but some begin to shut down around 5:00 - 5:30, or even earlier in winter.  In the dead of winter, it starts getting dark by 4:00 pm.