Often I saw this sign at highways in Germany:

Highway sign

Apparently it's not a regular traffic sign, but nevertheless I'm curious about its meaning. I tried to ask a local, but they also didn't know.

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    Tuxedo required Commented Jun 21 at 13:35
  • 2
    @CristobolPolychronopolis - This road sponsored by HSBC
    – Valorum
    Commented Jun 22 at 9:27

1 Answer 1


These signs are part of a test track for autonomous driving.

The German Wikipedia says in its article about the A9:

Teststrecke für autonomes Fahren

Abschnitte [der A9] in Bayern sollen als Testfeld für Innovationen im Bereich autonomes Fahren und Assistenzsysteme dienen. Das Projekt Digitales Testfeld Autobahn wurde im September 2015 initiiert. Ende 2016 wurden zwischen Pfaffenhofen und Kreuz Holledau spezielle Landmarkenschilder aufgestellt. Diese runden Schilder mit schwarz-weißem Muster dienen der zentimetergenauen Positionsbestimmung durch Kamera-unterstützte Navigation. Insbesondere kann so die Positionsgenauigkeit im regulären Verkehr anhand unabhängiger Fixpunkte gemessen werden.

Translation (using DeepL):

Test track for autonomous driving

Sections [of the A9] in Bavaria are to serve as a testing ground for innovations in the field of autonomous driving and assistance systems. The Digital Test Field Motorway project was initiated in September 2015. At the end of 2016, special landmark signs were installed between Pfaffenhofen and the Holledau junction. These round signs with a black and white pattern are used to determine the position to the centimetre using camera-assisted navigation. In particular, the position accuracy in regular traffic can be measured using independent fixed points.

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    "determine the position to the centimetre" I know that German engineering is legendary, but ground moves. Unless the posts are set in concrete footers below the frost line, it'll only take one good winter for them to have frost-heaved more than a centimeter and be out of alignment. Of course, they're Germans, so they may well have put appropriate footings down...
    – FreeMan
    Commented Jun 21 at 13:46
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    @FreeMan I wouldn't put it beyond the engineers to have DIN norm for that. Commented Jun 21 at 15:51
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    @Peter - Reinstate Monica: ak-doerr.com/ivz-norm
    – user24582
    Commented Jun 22 at 5:42
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    @FreeMan in Germany, the ground needs to fill out 4 different complicated official forms before it gets permission to move. Usually it doesn't bother. There, problem solved! Commented Jun 22 at 20:00
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    From my understanding: it's not meant for actually navigating, but for verifying whether the position derived by other measures is correct (as this is a "test track"). Commented Jun 23 at 0:14

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