Is there an equivalent to Route 66 available in Europe? Here I am not talking about the actual road with the number 66, but about a "trajectory" with a mythical connotation to its name. I did not follow route 66, but I guess due to its fame doing route 66 offer quite some touristic opportunities, compared to doing highway "john doe". I am aware of the international e-road network, but I am not so much interested in following one specific highway, more to do an interesting well documented road trip in Europe.
I suppose the only real European equivalent is the ill-defined 'grand tour'. But you'll be hard pressed to actually find it. Here's another question on the grand tour.
That said, there are plenty of semi-epic drives around Europe. In fact, much of Europe is so compact, that you can easily come up with your own epic ride in pretty much any part of Europe, without even having to drive too much.
The mythical, even mystical, route I think of, is not by car but by foot. It is not even a single route but a network of paths from everywhere in Europe to a single place: This is the Way of St. James.
I never heard of something close to Route 66 in Europe. Though car has an essential role in today's Europe, its history is relatively young. Famous paths are by foot or by train and they don't stop at the borders of Europe. Moreover, the most convenient way of travelling was not on ground but by boat. I don't think that the Mediterranean Sea or the Baltic Sea would qualify as the most famous routes. Garry Vass mentioned Orient Express and Marco Polo. Hippietrail mentioned Silk Road. There are also trade routes for spices, amber, and incense.
One path that is not so famous (yet) but that I would love to follow is the Eurovelo 6 from the Atlantic Ocean to the Black Sea, along the Loire and Danube rivers. It has only one 6 and only two wheels...
I agree with mouviciel. Europe's mythical road par excellence is the way of St. James.
If you prefer a drivable road, there is one particulary mythical road in France, the Nationale 7. It is nearly 1000 kilometers long and runs from Paris to Menton, on the French Riviera. It crosses some beautiful spots. The French also call it "route des vacances" (= holiday road). Before the construction of the motorway it was the main axis linking Paris and Southern France. There is a dedicated website.
You can also have a look at the Roman roads. The Romans built an extensive road network in Europe. These roads do not exist any longer. However, it should be possible to mimic their course today. Unfortunately, I think that such trips are not well documented.
You may be interested in Via Francigena too.
EDIT: I recently stumbled upon the European Institute of Cultural Routes and apparently its main purpose is to preserve, promote and improve historical/cultural routes in Europe. On the Wiki page there's a comprehensive list of the routes they monitor:
Major Cultural Routes of the Council of Europe
Cultural Routes of the Council of Europe
This article entitled Where is Britain's Route 66? gives possible suggestions for such a route in the British Isles including:
The Great North Road sounds like the beginning of an adventure. It links two great cities in London and Edinburgh. True to say that in its day, it had a selection of interesting eateries along its route, and much like Route 66, much of the original route has been bypassed, leaving quieter stretches to explore. Verdict: A genuine contender to the title of Britain's Mother Road.
If you stretch things a bit, you could claim that the A5 links London and Dublin, if you count the ferry. These two compare well with Chicago and L.A. It follows the route of the ancient Watling Street built by the Romans, hence it is signposted as 'Roman Road' along sections of its length. And there is plenty of things along the route indicating the route's history, such as coach houses and staging posts. The real trump card however is the Menai Suspension Bridge. This bit of architectural interest makes the A5 a stand out candidate. If only there was a song about it.
A book is also available for Britain's Route 66. It has over 900 colour photographs and the largest ever collection of memorabilia from the beginnings through today.
Available from Grantham Book services.
Tel: +44 (0)1476 541 080
(I have no association with the above book)
If you are a biker, you may be interested in Spain's own Route 66 with the Spanish company Route66Spain. They will introduce to:
A tour of Spain from north to south where you can enjoy the best scenery, sample the best restaurants and especially to make a unique and unforgettable experience in your life.
(I also have no association with this company either)