Highways in Spain

The Spanish motorway (expressways) network is the eleventh largest in the world by length,. As of 2013^[update], there are 16,583 km (10,304 mi) of High Capacity Roads (Sp. Vías de Gran Capacidad) in the country. There are two main types of such roads, autopistas and autovías, which historically differed in the strictness of the standards they are held up to.

The distinction between two kinds of high capacity roads is mainly a historical one, seldom with practical consequences for most but the oldest motorways. Both kinds are divided highways with full access control and at least two lanes per direction. General speed limits for both are mandated by the Spanish Traffic Law as 60–120 km/h (35–75 mph), though there are groups that ask for the latter to be raised to 140 km/h (85 mph). Specific limits may be imposed based on road, meteorologic or traffic conditions.

Autopistas are specifically reserved for automobile travel, so all vehicles not able to sustain at least 60 km/h (35 mph) are banned from them. Thus, they may not be an upgrade to an older road, since the Spanish legislation requires an alternate route to be provided for such vehicles. Many, but not all, autopistas are toll roads, which also mandates an alternate toll-free route (though not necessarily a freeway) under the Spanish laws. An example is the AP-2 toll autopista, which links Zaragoza with Barcelona through the Monegros desert. In this case, the alternative is the N-II, the national road that preceded the A-2 autovía.

On the other hand, autovías are usually (though not always) upgrades from older roads, and never toll roads. In general, slow vehicles like bicycles and agricultural machinery are allowed under certain restrictions so as to not disrupt the traffic excessively or cause any danger. Furthermore, an autovía will most likely follow the original road very closely, only deviating from it to avoid direct penetration into towns (which are looped around in variantes). Thus, the upgraded road usually serves as the base for one of the two directions of the new autovía, which means the turns can be steeper than in autopistas. All in all, an autovía:

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