I would really love to visit all 3 sites - Pompeii, Herculaneum, Vesuvius...but have a limited time schedule. Any comments on which of these is worth visiting and whether it's possible to squeeze 2 sites in one day? Also, how much time should I budget for visiting these locations. Thanks!

you could feasibly do Vesuvius in the morning, and Herculaneum in the afternoon. There used to be a bus from Ercolano station up to Vesuvius.

Pompeii deserves a day of its own.

i DID THEM ALL IN A DAY, i DIDNT KNOW IT WAS UNUSUAL, pOMPEI IN FACT AFTER ABOUT 2 HOURS i WAS BORED

Of the three, Pompeii is a must see. If you have two days you can do Pompeii one day and then Vesuvius and Herculaneum the second. It is not a stretch to do these two on one trip. You can hire a cab to take up Vesuvius. We squeezed 20 people into a 12 seater minibus. Fun going up the winding road up the volcano!

I haven't seen the others - but really enjoyed Pompeii. Beware of the heat - I'd recommend going as early as possible. We did the audio tour and stayed for two hours. Guides were more expensive, but probably worth it if you are with a group. I wish we had gone to the museum in Naples that has all the artifacts either before or after our trip.