The Frascati National Laboratories (LNF) are located 20 Km Southeast of Rome, near the town of Frascati.
Detailed instructions to reach LNF by the Rome Airports and "Roma Termini" central railway station can be found on the laboratory web page (click here).
Taxis are available at the airport or could be reserved from the secretariat upon request. They will take you to LNF in about 40 minutes.

Detailed Local Area Map of Frascati down-town, Villa Mercede (School Hotel) and INFN Laboratories is available here.