Answer : 4. "St. Petersburg, Vladivostok"
Explanation :

The trans-Siberian railway runs on a railway line spanning a length of 11,263 km in Russia. 

It connects St Petersburg located in western Russia with Vladivostok a city in the far East of Russia. 

It crosses eight time zones and the diverse topography of Russia. 

The Trans-Siberian Railway is the longest railway in the world. 

It was built between 1891 and 1916 to connect Moscow with the Far-East city of Vladivostok.