Explore details about location 国道４２１号. 国道４２１号 is a location situated within the 東近江市 alongside other areas such as 八日市五個荘線, 桜川西竜王線, 栗見八日市線. Additionally, some smaller parts of 国道４２１号 include specific areas like 中里山上日野線, 甲津畑山上線 adding to the diversity of its landscape.