The Hermitage is the largest collection of art in the world. It's set in the rooms and buildings of the Winter Palace, the former residence of Russian Czars up through Nicholas II. The baroque and roccoco architecture and interior alone is worth a visit! Located in the heart of St. Petersburg overlooking the Neva River, the Hermitage is a must see for any visitor to the city. Be aware that transport to the Hermitage is best accomplished by bus or taxi in bad weather or if you are unable to walk long distances. The closest subway stops (Gostiny Dvor or Nevskiy Prospect) are a fair ways away, but a nice walk in good weather.
Plan on allowing at least 2 days to fully take in all that the museum has to offer. Tours are available in many languages, including English, French, and German. The Hermitage has an excellent website here. There is an extra charge for using your camera or videocamera inside. As much of the museum is 'no flash allowed', you may find the camera to be a liability. Despite the admonitions, I noticed many locals using their flash--though I can't recommend it. Also, be prepared to check your coat in winter. It's required.
The exhibits are set up by geogrpahic location and time period, such as Oriental Art and Western European Art. The Hermitage is actually a collection of buildings, the largest of which is the Great Hermitage. It not within the scope of this review to describe all the art in the Hermitage. It is the largest collection in the world! Rather, rest assured, if you like an artist or type of art, there's a good chance that it's represented.
There is a cafe on-site and many vendors selling street food. However, you are very close to Nevsky Prospect and it's large selection of high-quality restaurants.