Kanazawa Seaside Line

The line grew out of plans to provide rail access to the large tracts of land being reclaimed along the Kanazawa shoreline. Construction was envisaged in Yokohama's comprehensive city plan of 1973 and again in the "Yokohama 21st-Century Plan" of 1981, and from 1983 the system was designed in line with the national "standardisation of new transit systems and their basic specifications" drawn up under the guidance of the Ministry of Construction and the Ministry of Transport. Civil works on the Namiki-Chūō–Fukuura section began on 15 November 1984.

The project was operated by Yokohama New Transit Co., Ltd., a third-sector company. To bring the line into service early, its Kanazawa-Hakkei end was opened with a temporary station, and the Kanazawa Seaside Line opened provisionally on 5 July 1989, linking Shin-Sugita with Kanazawa-Hakkei across the reclaimed waterfront.

Automation followed in stages. Automatic operation began on some trains in 1992, and from 1994 every train except training and test runs operated unmanned, making the line one of Japan's fully driverless urban transit systems. The original 1000 series cars were progressively replaced: the new 2000 series entered service on 26 February 2011, and the last 1000 series train ran in revenue service on 24 May 2014. On 1 October 2013 the operating company was renamed from Yokohama New Transit Co., Ltd. to the Yokohama Seaside Line Co., Ltd.

A long-planned improvement at the southern end was finally realised in 2019. On 31 March 2019 the permanent Kanazawa-Hakkei station opened, extending the line the short distance from its temporary terminus to a new station directly beside the Keikyū Main Line's Kanazawa-Hakkei Station and greatly easing transfers between the two railways.

Just over two months later the line suffered its most serious accident. At about 20:15 on 1 June 2019, a train at Shin-Sugita Station set off in the wrong direction and ran backwards into the buffer stop at the end of the platform; according to Japanese accounts fifteen passengers were injured, six of them seriously. Driverless operation was suspended and, from 4 June, the whole line reopened under manual control with staff aboard the trains. Automatic operation was restored on 31 August 2019, with weekend and weekday timetables returning to normal over the following months.

The extension works concluded on 14 February 2021, when the Kanazawa-Hakkei section was double-tracked, completing the project begun with the 2019 opening of the permanent station. Today the Kanazawa Seaside Line functions as a feeder for the Negishi Line at Shin-Sugita and the Keikyū network at Kanazawa-Hakkei, carrying commuters, students bound for the medical campus, and visitors to the Hakkeijima Sea Paradise along Yokohama's southern coast.

• 1973Construction of the line is envisaged in Yokohama's comprehensive city plan.
• 1981The line is again planned in the "Yokohama 21st-Century Plan".
• 1983Under the guidance of the Ministry of Construction and Ministry of Transport, the system is designed to the national "standardisation of new transit systems and their basic specifications".
• 198415 November: civil works begin on the Namiki-Chūō–Fukuura section (about 2.3 km).
• 19895 July: the Kanazawa Seaside Line opens provisionally between Shin-Sugita and Kanazawa-Hakkei, the Kanazawa-Hakkei end using a temporary station.
• 1992Automatic operation begins on some trains.
• 1994All trains except training and test runs become driverless (unmanned operation).
• 201126 February: the 2000 series rolling stock enters service under a timetable revision.
• 20131 October: the operating company is renamed from Yokohama New Transit Co., Ltd. to the Yokohama Seaside Line Co., Ltd.
• 201424 May: the last 1000 series train runs in revenue service.
• 201931 March: the permanent Kanazawa-Hakkei station opens, extending the line beside the Keikyū Main Line's Kanazawa-Hakkei Station.
• 20191 June, ~20:15: a train at Shin-Sugita Station runs backwards into the buffer stop; per Japanese accounts 15 passengers are injured, 6 seriously. Driverless operation is suspended; the line reopens under manual control on 4 June and automatic operation resumes 31 August.
• 202114 February: the Kanazawa-Hakkei section is double-tracked, completing the extension project.