In reply to jezb1:
I drove to Lofoten in the summer of 2015. We sailed Harwich to Hook of Holland and camped that evening. As far as I know that's still the nearest you can get a ferry. From there we drove to Hirtshals on the northern tip of Denmark - a full days driving, all on motorways but about 10-12 hours. Next morning a ferry to Langesund (cheapest and near enough shortest crossing to Norway) plus a lot more driving that day. Then about another 2 days driving to Lofoten, Norwegian speed limits are tediously slow and the fines enormous. Oh, and its also a hell of a long way! We stopped off at other places in each direction but only that were en-route anyway and we still clocked up 6,000 miles for the round trip.
Given that the Harwich ferry leave in the morning you'd have to drive down the day before so you're looking at about 5-6 days travelling in each direction. That doesn't leave long on Lofoten if you've only got 3 weeks.
We had 7 weeks away so it was worth the drive and way cheaper than flying + hiring a car for that long but for 3 weeks flying makes more sense.
If you are only intent on climbing on Lofoten you could probably get away without a car if the cost of hire is too high. There are a couple of semi wild camping areas each within walking distance of most of the crags and as ever in remote places, hitching is vey easy. There's hundreds of climbers driving about between the crags every day, have your rope visible and you won't have any trouble with lifts.
Post edited at 21:10