Border crossings are controlled and patrolled by the Finnish Border Guard and Border Guard Service of Russia, who also enforce border zones (0.1–3 km on the Finnish side, at least 7.5 km of Border Security Zone on the Russian side). Entry to a border zone requires a permit. The electronic surveillance on the Finnish side is concentrated most heavily on the "southernmost 200 kilometers" and is constantly growing in sophistication. The Finnish Border Guard conducts "regularly irregular" K9 patrols to catch anyone venturing into the border zone. Russia maintains its 500-year-old border patrol in the arctic region as elsewhere and plans to upgrade Soviet border technologies to both save on cost and to fully maximize the efficiency of the Border Service by the year 2020. However, Lieutenant-General Vladimir Streltsov, deputy head of the Russian border service, noted that electronic surveillance will never replace the human element.
The border can be crossed only at official checkpoints, and at least one visa is required for most people. Major border checkpoints are found in Vaalimaa and Nuijamaa, where customs services on both sides inspect and levy fees on imported goods.
The northern endpoint of the border between Norway, Finland, and Russia form a tripoint marked by Treriksrøysa, a stone cairn near Muotkavaara ( ). On the south, the boundary is on the shore of Gulf of Finland, in which there is a maritime boundary between the respective territorial waters, terminating in a narrow strip of international waters between Finnish and Estonian territorial waters.
The first border treaty concerning this border was signed in Nöteborg in 1323, between Sweden (to which Finland belonged) and the Novgorod Republic. The Treaty of Teusina in 1595 moved the border eastward. In conclusion to the Ingrian War, Sweden gained a large tract of land through the acquisition of the Nöteborg fortress, the Kexholm and its large province, southwest Karelia and the province of Ingria in the Treaty of Stolbovo (1617). The Treaty of Nystad in 1721 and the Treaty of Åbo in 1743 moved the border westward.
The main difference between the different sides of the border at the time was religion. The Russian side was Russian Orthodox, the Swedish side was Catholic, later Lutheran Protestant. Generally the native population was ethnically Finnish and Finnish-speaking immediately on both sides of the border. However, after the peace of Stolbovo in 1617, the Orthodox population was persecuted and either fled to Tver or converted to Lutheranism and started speaking Finnish instead of the closely related Karelian. The population was largely replaced by immigrants from Finland, most of which were Savonians.
After the Finnish War, the Treaty of Fredrikshamn converted all of Finland from Swedish territory to a Russian possession, the Grand Duchy of Finland. The Finnish–Russian border was moved back to the pre-1721 location, so that the Grand Duchy gained the so-called "Old Finland", territories previously held by Sweden, in 1812.
After Finland became independent in 1917, there was the Finnish Civil War in 1918, and even after this war, the Russian Civil War continued. Finnish activists often crossed the border into Soviet territory in order to fight in the "heimosodat", wars aiming at Finnish ethnic self-determination and possible annexation into Finland. However, this came to an end in 1920, when the Russian/Finnish Treaty of Tartu in 1920 defined Finland as independent and demarcated the countries' common border. However, Finnish fighters would still take part in the East Karelian uprising and Soviet–Finnish conflict of 1921–22. Finally, the Finnish government closed the border from the volunteers and food and munitions shipments in 1922.