Kolby is a village in Samsø Municipality, in the region of Central Denmark, Denmark. Kolby lies at 20 m above sea level. The nearest city is Aarhus, 45 km to the northwest. Among the landmarks around are Ilse Made kilde (4.2 km), Vesborg (3.3 km) and Brattingsborg Castle (4.3 km). Among the natural features are Dyret (4.9 km) and Lindholm (16.7 km).