A serious self-milling 100% buckwheat soba specialist, located about 18 minutes' walk from Gamo Station in Kawayanagicho, Koshigaya. The shop sources Botan-variety raw buckwheat from Rausu, Hokkaido, and handles all steps in-house—stone removal, polishing, and milling. The handmade 100% buckwheat noodles, made only with spring water from Shojinzawa (designated one of Japan's finest 100 waters) and buckwheat flour, are cut thin and feature a springy texture with rich aroma. The parking lot fills up almost immediately. Yahoo! Maps 3.92, Tabelog 3.59/126 reviews.

"The flavor of 100% buckwheat is outstanding—a level you rarely find elsewhere." "The pairing with tempura is exceptional." "The parking was full but waiting was absolutely worth it." "Mizusoba is a unique way to enjoy the natural sweetness of buckwheat." "It's a miracle to find soba at this level in Koshigaya."