The town's historic core, set on an island, is laid out around a 400m-long cobbled Rynek. It still operates as a marketplace on Tuesdays and Fridays, when stallholders selling local farm produce and piles of junk overrun its northern half.

Much of what you see was reconstructed after WWII, including the green house at No 29, where Napoleon recuperated after the Battle of Pułtusk.