Wanko soba was originally served in a bowl, and was originally served in a flat bowl for guests. Chopped leeks, bonitoes, grated radish, and nori (seaweed) are used as condiments, as well as sashimi of tuna.
People compete to throw a small amount of "kake-soba" into a bowl and eat it. The system for enjoying the large number of people eating is now called "wanko soba".