Clicking on a road or on a button will highlight that particular autostrada, and give some information on the distance between cities along the route. Click the highlighted autostrada again brings you back to the map of all the autostradas. A solid maroon highways is a "tangenziale" designed to get you around a major city. Usually tolls will not be charged on a tangenziale.
An autostrada is an Italian toll road. When you enter an Autostrada, look for a gate marked "Biglietto" (ticket) with a green light, where you will take a ticket. Don't enter gates marked "Viacard" or "Telepass" unless you have one.
Generally, you pay the toll at toll booths when you exit the autostrada or when the autostrada ends (when entering a tangenziale, for example). Usually, the tourist will look for the booths that allow cash payment, since some of the payment methods only work with Italian credit and debit cards or other means meant for residents. In major tourist areas (around Florence for example) there will be a sign directing "tourists" to the cash lanes. Hand your ticket to the person in the booth and pay the amount that comes up in the LCD panel near the window.
The maximum speed on an autostrada is 130 km per hour. There are speed traps, and recently the fines have increased for speeding. The posted speed may be slower, especially if road work is being done. You must drive with your lights on.
Autostrada tolls can be quite expensive. Usually there is a toll-free state road, or Strade Statale, that parallels the autostrada. Sometimes these can be quite slow going, especially if they pass through towns, so the tourist on a limited time budget may wish to use the faster roads.
Unlike in the US, the left lane of an autostrade is used for passing only, unless there is very heavy traffic. Drive on the right.
The official web site of the Italian autostrada system is Autostrade S.p.A, where you'll find limited information in English.
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