Gyöngyös is the side stream of the river Rába. It derives from Vörösvágás, and reaches Hungary at the height of Kőszeg, where it turns south. In Szombathely, it turns eastward again, and at Vasvár, it flows in the direction of northwest, Sárvár, where after about 90 km, it enters Rába. It is considered the most exquisite trout water in Hungary, primarily due to the ideal water temperature indicators.
Even during the summer months, the water temperature stays below 20 degrees Celsius, and the dissolved oxygen content is above 11 mg/l throughout the year. At almost any place, it is ideal to fish for trout and chub.
The Gyöngyös’ urban and non-urban areas, crossing the artificial landscape and the wilderness, are both popular fishing spots. Lukácsháza is a prominent cultural site (Sebes trout path). The Gyöngyös has an area of 25 hectares in Vas county. The number of fish species found in the stream is 22: trout, chub, bass and breams.