The Swedish Transport Administration upgraded 100 kilometres ( 62 mi ) of the line .
The Swedish Transport Administration built 30 kilometres ( 19 mi ) of new track , from Sundsvall to the connection with the new high - speed Bothnia Line north of Nyland .
The Swedish Transport Administration upgraded 100 kilometres ( 62 mi ) of the line , and built 30 kilometres ( 19 mi ) of new track , from Sundsvall to the connection with the new high - speed Bothnia Line north of Nyland .