Þrengslavegur is a road in Iceland that connects Route 1 to the towns along the southern coastline, whereas Þrengsli is a picturesque stream that runs along it.
These sites are often visited on Northern Lights tours due to the lack of buildings around here and thus the lack of light pollution. Those heading to the Westman Islands will also most likely travel down this route, as the ferries depart from Þórlakshöfn or Eyrarbakki. The nature here is largely of untouched lava fields, covered in moss in summer and snow in winter.
Þrengslavegur was built in the 1960s, as part of a larger infrastructure effort to better connect the nation.