東急東横線
Maps and station numbering use navy blue and the route symbol MM to identify the line. The entire line is underground and goes under the Minato Mirai and Kannai districts, and numerous islands made of soft reclaimed land and channels, requiring stations to be constructed deep underground. The original above-ground section of the Tōkyū Tōyoko Line between Yokohama and Sakuragichō stations was abandoned and replaced with a new underground connector line to allow through services onto the newly completed Minatomirai Line.