River Zala is the only river supplying Lake Balaton. It stems from the foothills of the Alps, near the Austrian border between Szentgotthárd and Őriszentpéter. It emerges from the three major branches accumulating from the Black Lake, the water of Sphagnum mossy marshland and many small sources. Through the Zala Hills region, it gets to Small Balaton, and finally, it flows into Lake Balaton at the southern part of Keszthely Bay, at Fenékpuszta, at 115 dpkm.

Along its way of nearly 140 kilometers, the small stream becomes strenghtened to a small river. It flows also through Zalaegerszeg and the Small Balaton, thereby making its image more colourful.