Peter the Great: His Life and World talks about the challenges of building St. Petersburg:
1703 was late in the history of Europe for the founding of a major city. By then, large towns and cities had sprung up even in Europe’s American colonies: New York was already seventy-seven years old, Boston seventy-three, Philadelphia sixty. And St. Petersburg, for 200 years the capital of the Russian empire, now the second-largest city of the Soviet Union, is the northernmost of all the great metropolises of the world. Placing it at the same latitude on the North American continent would mean planting a city of three and a half million on the upper shores of Hudson Bay.
Even traders who for centuries had used the Neva to reach the Russian interior had never built any kind of settlement there: It was too wild, too wet, too unhealthy, simply not a place for human habitation. In Finnish, the word “neva” means “swamp.”
Most of the new city was built of wood, and fires broke out almost every week. Attempting to contain the damage, the Tsar organized a system of constant surveillance. At night, while the city slept, watchmen sat in church towers looking out over the silent rooftops. At the first sign of fire, the watchman who spotted it rang a bell whose signal was immediately picked up and passed along by other watchmen throughout the city. The bells woke drummers, who turned out of bed and beat their drums. Soon the streets were filled with men, hatchets in hand, running to the fire. Soldiers who happened to be in the city also were expected to hurry to the scene. Eventually, every officer, civil or military, stationed in St. Petersburg was given a special fire-fighting assignment for which he was paid an extra monthly allowance; failure to appear brought swift punishment. Peter himself had such an assignment and received a salary along with the rest. “It is a common thing,” said a foreign observer “to see the Tsar among the workmen with a hatchet in his hand, climbing to the top of the houses that are all in flames, with such danger to him that the spectators tremble at the sight of it.”
One problem was that the region simply could not feed itself. The Neva delta, with its great stretches of water, forest and swamp, seldom produced good harvests, and sometimes, in wet years, crops rotted before they ripened. Wild nature was helpful; there were strawberries, blackberries and an abundance of mushrooms, which Russians ate as a great delicacy with only salt and vinegar. There were small hares, whose gray fur turned white in winter, which provided dry, tough meat, and wild geese and ducks. The rivers and lakes teemed with fish, but foreigners were chagrined to find that they could not buy it fresh; Russians preferred fish salted or pickled. But despite what could be gleaned from soil, forest and waters, St. Petersburg would have starved without provisions sent from outside. Thousands of carts traveled from Novgorod and even from Moscow during the warmer months bringing food to the city; in winter, the lifeline was maintained on a stream of sleds. If these supplies were even slightly delayed along the way, prices immediately soared in St. Petersburg and in the villages nearby, for, in reverse of the normal process, the town supplied its satellites with food. In the forest around St. Petersburg, an endless horizon of scraggly birches, thin pines, bushes and swamps, the traveler who ventured off the road was quickly lost. The few farms in the region lay in clearings reached by unmarked paths. And in these thickets and groves roamed bears and wolves. The bears were less dangerous, for in summer they found enough to eat and in winter they slept. But wolves were plentiful in all seasons, and in winter they appeared in aggressive packs of thirty or forty. This was when hunger drove them to enter farmyards to catch dogs and even attack horses and men. In 1714, two soldiers standing guard in front of the central foundry in St. Petersburg were attacked by wolves; one was torn to pieces and eaten on the spot, the second crawled away but died soon after. In 1715, a woman was devoured in broad daylight on Vasilevsky Island, not far from Prince Menshikov’s palace.
More: read Peter the Great: His Life and World
While wild blackberries are common in that region, I doubt they can be relied on for subsistence. More likely – especially to go along with wild strawberries – that it was wild bilberry that they picked.