Traffic on the Citybanan line, which has only been open since July, closed at 3pm on Tuesday due to a technical problem with safety doors, with no indication of when the problem would be fixed.
But to the relief of Stockholm commuters, it reopened by rush hour on Wednesday.
"Everything is back to normal. The City and Odenplan stations are open," Thomas Silvander, a spokesperson for Stockholm public transport operator SL, told the TT news agency.
The new Stockholm City and Odenplan stations, which were closed on Tuesday, were built for the purpose of Citybanan. On Tuesday trains instead used the old route through Karlberg and T-Centralen.
This meant they were using the same lines as intercity trains, which caused some delays and cancellations.
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