When you travel in Japan, you can find udon menu in many restaurants such as Japanese restaurants, udon restaurant chains and restaurants which serve udon menu only and are operated by individuals. If you can search privately run udon restaurants on the internet during your travel, I recommend you to go there. In addition, I recommend you to go to restaurants which make noodles and soup stock there because they serve very delicious udon rather than udon in restaurant chains. They also serve many kinds of toppings for udon. It is udon with burdock tempura and simmered beef in the picture.