The Eurotunnel is located underneath the English Channel. Instead of taking a ferry or airplane across the channel, you can choose to drive the tunnel.
To travel on the Eurotunnel, you must have a valid passport to enter France and England. You must check in with proper documentation, including insurance, a half-hour before departing. You can check in at the booths or a self-check machine.
Check the Eurotunnel website for information on the times cars depart England or France. During peak hours there are up to four departures an hour. Keep in mind that when you arrive in the other country you must meet their vehicle requirements (such as headlight height) and driving laws.