35 miles taking this route:
About 3 quarters of a hour excluding traffic which is normally quite bad x
30 miles as the crow flies, slightly more on the motorway.
No. You can get a tube train from Heathrow into central London and then an overhead train from London to Luton.
The closest main airport to Oxford is Heathrow. Luton, Gatwick and Stansted are all much further and roughly the same distance from Oxford.
There are no trains between Luton and Heathrow but there is a shuttle bus service.
They are all airports near London.
36 miles
From London (Heathrow) to Otopeni: 3 h 30 min. Luton is near London.
About 40 miles
about 45 minutes
The main airport is Heathrow. The secondary airport is Gatwick.
There is no regular and direct flight between Cardiff to any airports in Bulgaria. One has to make a stopover somewhere (may be to some British Airports like Heathrow, Luton). From Heathrow and Luton there are regular flights to Sofia-2 Airport. Running flight time from London/Luton to Sofia is around 4 hours (in medium size jet)