It's a 1 1/2 to 2 hours when driving from either location
Depends where in Hertfordshire you're starting from.
Northwest London adjoins the county of Hertfordshire, so it would depend on which part of northwest London and which part of Hertfordshire.
It is approximately 120 miles.
The shortest driving distance is 98 miles.
Hertfordshire
Joanna Garland by far
192 miles 3 hours and 17 minutes
Memphis is about an hour drive from Oxford
About 65 miles. Oxford isn't in London.
It is 31 miles from Dallas, TX to Oxford, The Colony, TX.
59.4 miles
106 miles