I would love to do food related travel. Please inform me of where and when the best festivals related to food exploration and your experiences travelling in North America & or Europe.
The Fete des Vendanges de Monmartre in Paris celebrates the harvest of over 1200 wines and has the best cheese displays and artisinal breads and local food to be found in France. It's only one weekend at the Sacre Couer....fabulous.
I've been to quite a few food festivals and one of my favorites has got to be the Eat Real Fest in Jack London Square in Oakland, CA, every September. It's been going on for about 5 years now. It's a three day festival over a long weekend with all the best local food trucks and restaurants serving there. It's really big and goes through the entire area of Jack London Square. What I like is that everything is $5 so you can sample a lot of different foods. Bonus points that it's super close to San Francisco which is worth a vacation in itself.
Another very popular one that has been taking place every summer is the Garlic Festival in Gilroy, about a 2-3 hour drive from San Francisco. I've been coming here since I was a little kid and remember the garlic froyo fondly.
Further south is the Avocado Festival that has also been going on for several decades in Carpinteria close to Santa Barbara. Never been, but my friends and I want to road trip down there for it one of these years!
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Menton in southern France has their annual Lemon festival in Late February.
Fallbrook, CA, a but north of San Diego on I-15, has their annual Avocado festival in mid-April. I went to that last year, it was nice, but wish there were more vendors selling avocado foods...guacamole was only available from one vendor who had multiple booths! Not much to compare...
Late September into October are always a great time for food festivals, especially surrounding the harvests of wine grapes, truffles, etc. in the Mediterranean regions of Croatia, Italy, etc. The truffle festival in Livante, Istria (Croatia) was a lot of fun when I made it there in October, 2013 (I got there just as the white truffle season / festival was beginning). Lots of great wines to try, and the truffles were very nice.