Speed limits in Germany
In 1973, in the wake of the 1973 oil crisis, a federal speed limit of 100 km/h (62 mph) on Autobahns was imposed to help conserve fuel for fear of impending future shortages (not for environmental or safety reasons). The measure only lasted from December 1973 to March 1974; while the administration and the Bundestag were in favor of keeping the speed limit, the Bundesrat pushed to repeal the law. As a compromise, a "recommended speed" was introduced on Autobahns and "highways outside of built-up areas with a center divide or without a center divide and a continuous lane for overtaking in both directions". This law is basically still in effect today. Unrestricted non-Autobahn highways, however, have since become virtually non-existent or replaced by "Schnellstraßen", Autobahn-like expressways typically limited to 120 or 130 km/h and normally only covering a few kilometers.
Controlled-access highway
The Spanish network of autopistas and autovias has a length of . "Autopistas" are specifically reserved for automobile travel, so all vehicles not able to sustain at least are banned from them. General speed limits are mandated by the Spanish Traffic Law as . Specific limits may be imposed based on road, meteorological or traffic conditions. Spanish legislation requires an alternate route to be provided for slower vehicles. Many, but not all, autopistas are toll roads, which also mandates an alternate toll-free route under the Spanish laws.