It is a busy rail junction located on the international Warsaw–Białystok–Grodno line, with additional connections which go to Suwałki and the Lithuanian border.

In 1861, Walery Wróblewski came to Sokółka and founded a secret organization in preparation for a Polish uprising, which broke out in 1863.

[3] In 1873 Sokolka was the birthplace of Alexander Bogdanov, polymath and revolutionary, who was a serious rival to Lenin for leadership of the Bolshevik Party in its early years.

Several Poles from Sokółka, including the town's mayor, were murdered by the NKVD in the large Katyn massacre in April–May 1940.

The Jews of all surrounding villages and towns including Krynki, Janów, Czyżew, and Zaręby Kościelne were kept there.

[9] On 24 July 1944, troops of the 2nd Belorussian Front of the Red Army dislodged the German occupying forces from the town.