10 March 1990: Third stage opened between Tokyo & Shin-Kiba; and the new Keiyo Line train, the 205 series, was also introduced to the public.
10 Maret 1990: Bagian ketiga dibuka antara Tokyo & Shin-Kiba; dan kereta Jalur Keiyo yang baru, 205 series, diperkenalkan kepada umum.