|Owner||Yokohama Minatomirai Railway Company|
|Line length||3.4 km (2 mi)|
|Track gauge||1,067 mm (3 ft 6 in)|
|Electrification||1,500 V DC overhead catenary|
The Kodomonokuni Line (こどもの国線, Kodomonokuni-sen) is a railway line in Kanagawa Prefecture owned by the Yokohama Minatomirai Railway Company and operated by Tokyu Corporation.
The line opened in April 1967, at the same time as its 'parent' station, Nagatsuta. It is a single track local line designed principally to cater for visitors to Kodomonokuni Theme Park (Children's Land) park. Consequently, the two-car trains are particularly busy during summer weekends and holidays.
The line originally was built and opened as a transportation link to the park (which opened in 1965) from the Tōkyū Den-en-toshi Line. The Children's Land Association (Shakai Fukushi Houjin Kodomonokuni Kyokai) owned the right-of-way and the Kodomonokuni Station, but the actual operation was contracted out to Tokyu Corporation.
In 1997, the line was sold to Yokohama Minatomirai Railway Company (MMR), a joint venture of Tokyu Corporation, the Kanagawa prefectural government and the Yokohama city government. In 2000, an intermediate station, Onda, opened in Aoba-ku, Yokohama to reflect the changing role of this line as a commuter line. MMR today owns the right-of-way, Kodomonokuni and Onda stations and the rolling stock, but the actual operation continues to be contracted to Tōkyū.
Local residents along the train line have expressed an interest in getting the Kodomonokuni Line extended northward to meet the Odakyū Odawara Line at Tsurukawa; however the planning has not yet taken off because the proposed rail alignment, despite its short distance, involves two prefectures (Kanagawa, Tokyo) and three cities (Aoba-ku, Yokohama; Asao-ku, Kawasaki and Machida, Tokyo).
The travel time from Nagatsuta to Kodomonokuni is 7 minutes (with one stop at Onda). At both Kodomonokuni and Nagatsuta stations there are ticket machines for this line, but the Kodomonokuni Line shares Tōkyū platforms at Nagatsuta.
Trains depart every 20 minutes throughout the day (every 10 minutes between 8 and 9 a.m. both directions) and at weekends; however, services are more regular during morning and evening peak times, and during Golden Week.
All stations are located in Yokohama, Kanagawa Prefecture.
All trains are based at Nagasuta Depot, accessed via a spur located before Onda Station.