The Best Guess: Just Go Out Early and Take a Taxi.
As of March 2015, getting to the Mariinsky can be a tricky thing. The old house and the second stage are in less than 5 minutes of walking distance from each other. Even though they are both well served by buses coming from West, most hotels are to the East of the opera houses. Moreover, there is no Metro (subway) station in less than 20 minutes’ walking distance from the Mariinsky. Unless you (1) are planning on leaving to the opera 2 hours before curtain time, (2) are bringing a smartphone with an Internet connection, (3) speak good Russian and (4) the weather is good, believe me—you would be better off by taking a decently-priced taxi.
Taking the Metro?
The current best alternatives for taking the Metro are Sadovaya, Sennaya Polschad, Spasskaya and Admiralteskaya. However, these are not totally advisable because—again—they are at 20 minutes’ walking distance from the theatre. Unless you have a smartphone and an Internet connection, you will most likely get lost and probably be late for the performance. Latecomers will sit in Balcony until the first intermission. Also, one needs some time to calm down before seeing an opera; running 5 minutes before the opera is usually not a good idea. Unfortunately, I’m talking from experience. Check my Sad Stories below for illustration.
This information is to be updated because there are now plans to extend the Metro service to the opera houses, which usually receive some 4,000 visitors every night. If when you go to St. Petersburg you do find a Metro station called Teatralnaya—that will be your stop.
The Easy and Safe Way to Use Public Transportation.
Saint Petersburg has public transportation everywhere. There is the Metro; there are regular buses and marshrutkii. All those options are fairly priced and will beat the price of any taxi hands down. If you are planning on taking public transportation, I advise you to install a free app called WikiRoutes. It will only work with an Internet connection. Click on the magnifying glass; on field A, choose моё местоположение (“my location”) and write “Teatralnaya ploshchad’” on field B. When you have an Internet access, the app will give you the instructions on the best combinations of buses and marshrutkii to the Mariinsky. You may want to get acquainted to pictures of the opera houses, which you can find abundantly on Google. Unless you can do all this or get very specific and easy instructions from the hotel desk on how to get to the theatre, I again advise you against taking the metro or a bus.
A Word of Advice on Taxi Services.
In Russia, everyone who drives a car is a potential taxi. Unless you have proficient skills in Russian, if you flag down a taxi in the street, there is a 99% chance that you will be overpriced. In my first days in Russia, I got to pay 10 times the normal fare for some small rides. The only way one can go around this is by calling reputable taxi companies or by having them called by your hotel desk. From experience, I can say this will still often lead to overpricing and other delays. If you have a smartphone, I strongly advise you to install the Uber app. You can choose any language you want and it will get you decently priced taxis which you can spot on a map of the city and then rate the service. You can choose your pickup location and your destination directly on the map. You will have to provide your credit card info to the company for automatic debits, which may sound scary, but this is actually rather safe because the company is U.S.-based. The invoices will be sent to your email address. However, you must have an Internet connection to access the app—either at your hotel or at the Mariinsky’s free Wifi. Though the service is not flaw-free, I would say it worked for me in 90% of the cases—and that still beats other taxis hands down. If you do embrace Uber, I also advise you to call it to the old Mariinsky because it is difficult for them to stop in front of the Mariinsky-2.
Should you have no alternative to flagging down a so-called “gypsy taxi,” keep in mind that if you are in a touristic area, 300 rubles is considered overpricing as of March 2015 and you won’t pay less than 150 for sure. Don’t walk into a taxi with more than one driver; if you take a gypsy taxi, do so at your own risk.
The Mikhailovsky.
This is the exception. If you’re going to the Mikhailovsky, I advise you to take the Metro and walk 5-10 minutes from the north exit of Gostiny Dvor. The opera house is downtown just outside the Russian Museum and near the famous Nevsky Prospect. However, a taxi might be a good idea if it is very cold outside.
Read my Sad Stories