The precursors to postal stations appeared during the reign of Ivan III (1440–1505) and were called yams.
The yams were located 30–50 versts (32–53 km) apart and were intended for changing horses and providing rest for travelers.
They consisted of a small settlement with 2–3 huts, stables, and sheds.
The distance between yams was called a progon, and a specific fee was charged for each progon.
To travel along a postal route, one first had to obtain a podorozhnaya.
This travel document specified the route, which could not be deviated from, as well as the traveler’s rank.
It also allowed one to change horses at any yam or settlement along the route.
After Peter I introduced the Table of Ranks in 1722, the number of horses available depended on the traveler’s rank: representatives of the first class of the Table were entitled to twenty horses, third-class holders to twelve, and “lower ranks and servants” to only two.
Under Empress Catherine II, the postal station replaced the yam.
In addition an official postal service staff was introduced.
Instead of lifelong yamshchiks (postal coachmen), postal workers were hired freely, and a unified postal route was established across the country.
From 1831 to the mid XIX century, tenders for the maintenance of postal stations were held every fifteen years.
Anyone could own a station — the bidder who paid the highest fee to the treasury won.
The owner was required to keep 25 horses at the station, 10 carts or sledges, and all necessary equipment for postal workers and mail transport (horse harnesses, trunks, bags, saddles, etc).
Despite the invention of railroads in the early 19th century, postal stations continued to be used in some regions of Russia until the 1920s.