Minoan Line ferries run from Venice to Greece. Not been on them but passed them whilst in Venice. You apparently sleep in your Caravans or Camper van, they have overhead electric hookups. Obviously not the shortest route but save on road time going down through Italy.
Do you want to go to Corfu or Igoumenitsa? Patras is the better port for the Greek heartland. I've nothing against Igoumenitsa (or even Corfu although it's a long way to travel for a very 'touristified' island!) but if you want to see the great Greek sites then Patras is much better.
So I can only talk about journeys to Patras although most of those ferries call at Corfu at dawn and Igoumenitas late morning. Which route you choose depends, of course, on cost but also on how much time you want to spend driving. It's a long drive to Brindisi and the crossing isn't much shorter than the one from Ancona which is the one we've used most recently. As mentioned the route with the lowest road time is to get a ferry from Venice although we found that both expensive and time-consuming in the past - but haven't tried it for several years.
Jens, have you considered driving down via Serbia and Macedonia. I found people in Serbia very helpful and the scenery is impressive if you plan the route accordingly. If you want to go via Italy I would use Ancona as a departure port because Bari is a long drive south and at least you will get a chance to relax on the ferry from Ancona.
------------- 'A sure cure for sea-sickness is to sit under a tree'
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Find out if you can use your van to sleep in - if not, have a grab bag made up with a kip mat, sleeping bag, some water and food and as soon as you get on board head for the highest deck - throw you gear on a bench, get on top of it and go to sleep - DON'T MOVE FOR ANYONE - people willl try to wake you move you etc but ignore them. They will eventaully drift off and bed down on the decks.... at 0300hrs the crew usually comes around with hoses to clean the decks
Last April we went on a new one (for us) - Bari - Patras. Great overnight ferry with very good food &c.. Bars was a nice place to look around too.
We had a great, longish holiday in Greece but I won't go on about it because we didn't camp! It is a lovely country and we had no problems with money or anything else.
Just a note about both Brindisi and Bari - Don't leave your Motorhome unattended at any time. You do need for at least one of you to be with the vehicle at all times
We used the Ancona to Patras route last year. It stops on route at Igoumenitsa, we were given same price for either destination.
We had thought it would be considerably more expensive from Ancona than from Bari but price was over £50 cheaper and saved driving a further 400 km
We didn't book, just turned up at Ancona dock. At the Superfast Ferry counter (just a name not any faster ferry) we were given a price of €450. The counter next to it was Mimoan Lines, a quick stop there and they offered $252. As camping on-board wasn't available they gave us a complimentary cabin and meal vouchers for 2 days breakfasts and evening meals.
Ferry left 2 hours later, have nothing but good to say about the company and the ship. Sadly we sailed the day another ferry caught fire in the Adriatic so our ship was diverted for over 30 hours for the rescue of the passengers who helicoptered onto our ship.
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