The Toriibira district of Katsunuma Town, is located on a south-facing slope at an altitude of 450 meters, and has been regarded as the best single vineyards of Katsunuma. Koshu in the hills is naturally limited in yield compared to grapes grown on the valley floor. The grapes at Toriibira are smaller, more condensed bunches, with a higher concentration of fruit flavours and balanced acidity. The soil mixed with gravel and black slate is well-drained,
The “Koshu Toriibira Private Reserve” grapes are carefully selected, with the top selection fermented in old French oak barrels (30%) and in a stainless steel tank.