pointing the way to the nearest one. Despite the increasing use of mobile phones, there are still about 150 calls made each day on average (after some 700 in 2013). This still equals four calls per kilometre each year. The location of the caller is automatically sent to the operator. Parking, rest areas, and truck stops For breaks during longer journeys, parking sites, rest areas, and truck stops are distributed over the complete Autobahn network. Parking on the autobahn is prohibited in the strictest terms outside these designated areas. There is a distinction between "managed" and "unmanaged" rest areas. (German: bewirtschaftet / unbewirtschaftet). Unmanaged rest areas are basically only parking spaces, sometimes with toilets. They form a part of the German highway system; the plots of land are federal property. Autobahn exits leading to such parking areas are marked at least (mostly ) in advance with a blue sign with the white letter "P". They are usually found every few kilometres. Some of them bear local or historic names. A managed rest area (German: Autobahnraststätte or Raststätte for short) usually also includes a filling station, charging station, lavatories, toilets, and baby changes. Most rest areas also have restaurants, shops, public telephones, Internet access, and a playground. Some have hotels. Mandated every or so, rest areas are usually open all night. Both kinds of rest areas are directly on the autobahn, with their own exits, and any service roads connecting them to the rest of the road network are usually closed to general traffic. Apart from rare exceptions, the autobahn must not be left nor entered at rest areas. Truck stops (German Autohof, plural Autohöfe) are large filling stations located at general exits, usually at a small distance from the autobahn, combined with fast food facilities and/or restaurants, but have no ramps of their own. They mostly sell fuel at normal price level while the Raststätten fuel prices are significantly higher. Rest areas and truck stops are marked several times as motorists approach, starting several kilometres in advance, and include large signs that often include icons announcing what kinds of facilities travellers can expect, such as hotels, filling stations, rest areas, etc. Speed limits Germany's autobahns are famous for being among the few public roads in the world without blanket speed limits for cars and motorcycles. As such, they are important German cultural identifiers, "often mentioned in hushed, reverential tones by