Sotobō Line
A railway line in Chiba Prefecture, Japan, operated by JR East. The name refers to the outer (Pacific) side of the Bōsō Peninsula.
I went from Chiba to Katsuura on the Sotobō Line.
Compound of 外 (soto, 'outside') + 房 (bō, abbreviation of 房総 Bōsō Peninsula) + 線 (sen, 'line').