As an Icelandic resident that has done that flight many times in rw it looks like you were landing runway 19
Looks like you might be right about runway 19 and my apologies for misidentifying the runway as runway 13.
And re-examination of the Google maps show me that you are correct about highway route number 1 Þjóðvegur. But I believe I passed the town of Grundarhverfi based on your correction, not Akranes. Please confirm if this is correct or not.
Once again many thanks for correcting me and my apologies to you and anyone for misidentifying runway number and approach path. Sometimes Google maps FOOL me.
Regards,
Aharon