Hyiyamugi are wheat flour noodles similar to somen. Somen and Hiyamugi are same ingredient and taste, but their size(especially thickness) is just different.
In Japan, people usually eat Hiyamugi during summer. It can be cooked as both cold and hot noodles and easy to eat. Cold style has two different kinds - dipping noodles in the tsuyu or pouring tsuyu on noodles. Tsuyu is a source for Soba, by the way.
Here is a picture I cooked poured hiyamugi with syabu-syabu pork, Japanese brassica(Mizuna green) and onion (leek onion).
