Taking a train is definetly very easy and convinient to go for day trips in towns near Rome. It's also very cheap! Plus, it's so senic, it's almost an experience on itself!
Termini, the main train station in Rome, is a huge modern complex and integrates well with the bus staion in the piazza just outside and the metro links.
tickets for 2 on the leonardo da vinci express from the airport to roma station costs 34,000 lires. you can purchase it from machines with credit cards or cash. remember to validate it though!
For all your connection with the train.
Go to Statione Termini.
Around th station there are a lot of Cheap Hotels and B&B.
The best way to get from Rome to Tivoli is by Train from Termini station. The rest of the city is easy to reach by bus or underground.
It as even possible to do a lot on foot.
We was coming with train to Rom, it was adventuarally. In Rom the people are driving with little rollers, very great. Are driving to work, for shopping, for culture ...
Almost all modes of transport come to Roma Termini. trains from the Fiumocino Airport, buses, metropolitana, taxis all have their stops here.