Article snapshot taken from Wikipedia with creative commons attribution-sharealike license.
Give it a read and then ask your questions in the chat.
We can research this topic together.
The Tamsui–Xinyi or Red line (code R) is a metro line in Taipei operated by Taipei Metro. It is named after the districts it connects: Tamsui and Xinyi. It includes a total of 28 stations serving the Tamsui, Beitou, Shilin, Datong, Zhongshan, Zhongzheng, Daan, and Xinyi districts. At 29 km (18 mi), it is currently the longest line of the Taipei Metro.
The Tamsui section runs mostly along the former Tamsui railway line. Most of the tracks and stations have been renovated there, except in the Zhongzheng district, where a new tunnel was constructed due to a lack of surface right-of-way.
The Red line is a high-capacity rapid transit system. The route and stations between and including Minquan West Road and Xiangshan are underground; the routes and stations between and including Yuanshan and Beitou are elevated; Xinbeitou station is elevated; the route and stations between and including Fuxinggang and Hongshulin are ground level; and Tamsui station is elevated.
For 15 years, trains operated between Tamsui and Xindian via the southern part of the current Songshan–Xindian line, making it the longest-serving former service of the system, followed closely by a 13 year service from Beitou to Nanshijiao via the southern part of the current Zhonghe–Xinlu line. With the completion of Dongmen station, Xinyi Line, and Songshan Line, both services ended, placing the current form of the Tamsui–Xinyi line into effect.
July 1988: Tamsui Line begins construction.
28 March 1997: Tamsui Line begins service from Tamsui to Zhongshan.
11 November 1999: The rest of the Xindian Line opened. Trains from Tamsui traveled to Xindian and the Zhonghe Line route was cut back to Beitou.
1 November 2002: Ground broken on Xinyi Line construction.
12 February 2010: Corridor approved by the Executive Yuan for the Xinyi line eastern extension.
15 July 2010: The last section of shield tunneling is completed, marking the completion of tunnel construction.
29 September 2012: With the opening of Dongmen the last trains between Beitou and Nanshijiao were launched ending the through services; trains now operate between Nanshijiao and Huilong or Luzhou. A new shuttle service from Beitou to the Taipower Building was added temporarily until the Xinyi Line opened.
15 October 2013: Xinyi line completed its preliminary inspection.
23 November 2013: With the opening of the Xinyi line, the last trains of the Beitou-Taipower Building shuttle service were launched; trains operated between Beitou and Xiangshan and between Taipower Building and Ximen via the Xiaonanmen line.
24 November 2013: The section between Chiang Kai-shek Memorial Hall and Xiangshan opened and began revenue service.
14 November 2014: With the opening of the Songshan line, the last trains between Tamsui and Xindian were launched at 12:00 on November 15, 2014 ending the through services; trains now operate between Xindian or Taipower Building and Songshan and between Tamsui or Beitou and Daan or Xiangshan.
September 2019: With the platform gates at Fuxinggang Station (August 2018) put into operation, all platform gate projects on this route have been completed.
20 June 2019: The "Xinbeitou-Da'an" shuttle service begins its trial operation.