Italy's Adriatic coast

Urbino is a jewel of a small city. We also liked Ascoli Piceno. We had a car, so I can't really address the issue of transport access. The Frasassi Caves are quite spectacular.

The Adriatic coast is 1000 km long. You can't visit everything from one base. Where exactly do you want to visit? Puglia? Marche? Abruzzo? Trieste? Besides Venice, the most beautiful area along the Adriatic coast is, in my opinion, Puglia (the heel of the Italian boot). That's quite a distance from Venice though.
The Marche region is also nice (that would be the region suggested by Rosalyn).

If I were doing the Adriatic, I'd go to the Croatian side instead.

We traveled the Adriatic coast of Italy for 3 weeks in 2012, via public transportation. But as Roberto said, it's much too long for one home base. We stayed in five places:

Senigallia, in the Marche -- a picturesque little town with a couple of Michelin-starred restaurants and miles of sandy beach. It will likely be too cool for swimming in April or May but if you like to walk along the sand in the morning, or to sit by the sea with a glass of wine after a busy day of sightseeing, you'll love it. It'll be quiet this early in the season with very few tourists but you'll still find great food. Our day trips: the little hill town of Corinaldo and the Caverns of Frasassi.

Then we took a train south to Trani, a picturesque little harbor town. Day trips included Castel del Monte and the salt plains at Margherita di Savoia. Had some great food here.

We then took a train to Bari and another train to Matera, which is not on the Adriatic but is a must-see, if you're this close. It's an ancient town, one of the most unusual places you'll ever visit, and a World Heritage sight. You can stay in a cave hotel. Two nights here is good.

We rented a car when we left Matera and spent the next six days at Masseria Montenapoleone, near Pezze di Greco. A masseria is similar to an agriturismo. This was our favorite part of Puglia, with the trulli villages of Alberobello and Cisternino, and the beautiful little towns along the coast. A masseria is a great experience ... and you'll find them all over this area. A car is really helpful to roam but when we were debating a car, we had figured out how to go from Matera to Alberobello by bus.

We returned our car in Brindisi and took a train to Lecce for our final stop. We were disappointed in Lecce but enjoyed our day trips around the boot: Otranto, which was dead off-season (we were there in late October) and beautiful Gallipoli .. a really picturesque little fishing village. We wished we had stayed there instead of Lecce. We took a winery tour one day with a company called Experience Path -- highly recommended.

At the end of our trip we took a train to Brindisi, flew to Milan and then home.

There's so much to see along this coastline that you'll have to make some difficult choices. No matter where you go you'll find wonderfully kind people, great food and wine, and spectacular scenery. Get out a map, and Google the interesting places, and come back here when you have more questions.

Neither Urbino nor Ascoli Piceno are on the coast, but if you have several bases, you can certainly get to each of them. You could fly into Venezia and out of Bari. How much time do you have?

Thank you all, for all of your information. After reading your posts, it is obvious that we can't stay in one spot, if we plan to cover a good bit (but not all) of the coastline. Also, it sounds as if we will need a rental car. We will have 2-3 weeks for this trip. Thanks.