It is possible to take a train from Rome to Pescara and then from Pescara to Vasto, which is nearby, but difficult to get from Vasto to Palmoli without a car. Although there are buses, I would suggest renting a car at whatever airport you fly into. If you have a group of people coming at the same time, arrangements can be made for pickup at the airport and for some tour services. Go to the Services page or contact me for more details at info@palmch.com.
To get here from Rome the easiest way (although admittedly a little longer), take the A24/A25 Autostrada - Rome to Pescara. Then, take the A14 Autostrada from Pescara to Vasto. Exit at Vasto Sud and take SS650, also known as the Trignina, towards Isernia. Look for the exit for Dogliola, Palmoli, and from there, follow the signs to Palmoli.
The shorter way is to take the A1 Autostrada (Rome to Napoli), exiting at the San Vittore exit and heading towards Venafro. From Venafro, you will follow the signs towards Isernia. Once in Isernia, you will go towards Vasto/San Salvo on SS650. Look for the exit for Dogliola/Palmoli, and from there, follow the signs to Palmoli.
Here's a map to give you a general idea of where we are....