Whenever i search for the physical location and path of WAN connectivity, i only find submarine cables, and a site that seems like a paid service. Is there no free map where i can e.g. show the route that the connection from, lets say, Prague to Lissabon takes? Im quite suprised that such a trivial thing seems to hard to find out. So my question is - why is there no map of the most relevant, large continental internet cables, while there is a map for submarine cables? Is there some sort of instance that overlooks the most important cables, like the TAT-14 commitee?

  • Unfortunately, product or resource recommendations are explicitly off-topic for SE sites, except Software Recommendations and Hardware Recommendations. Also questions about networks you do not directly control are off-topic here.
    – Ron Maupin
    Commented Apr 17, 2019 at 12:47
  • Would you care to explain on what site this would not be off-topic? For such questions that arent extremely special i would find it very sad if they would be off-topic without an alternative place to ask them being present. Commented Apr 17, 2019 at 13:24
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    The only question in your post is, "Is there no free map where i can e.g. show the route that the connection from, lets say, Prague to Lissabon takes?" That would either be a simple Yes/No answer, or it is soliciting a resource. Remember that the Internet is just the ISPs connecting to each other in whatever fashion each wants, and the connections change and traffic is rerouted all the time. That was the reason for the Internet: to automatically route around damage. You would need to ask each ISP how it connects to its neighbors, and ISPs can change neighbors as they want.
    – Ron Maupin
    Commented Apr 17, 2019 at 13:40
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    No, you seem to be under the mistaken impression that many people are. There is no "Internet backbone".
    – Ron Maupin
    Commented Apr 17, 2019 at 13:52
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    There are such maps, but they aren't public for many reasons. The owners of the lines generally have pretty detailed maps, but they're internal trade-secret documents. Some government offices will have less detailed maps for coordination/management reasons -- "call before you dig" stuff, but they don't share those either. As a property owner, I have some idea what's buried across my land -- not all of it makes sense, and it's only a very small chunk of the overall puzzle.
    – Ricky
    Commented Apr 17, 2019 at 18:01

1 Answer 1


Trivial? I'm not so sure.

You'd have to ask many people at many service providers (and in turn their service providers, and then their (dark or lit) fibre providers and then their cabling companies) about many many details, most of which they won't, can't or must not make public.

You might be able to get some high-level diagrams (as in: a powerpointable JPG showing a country or half a continent with some dots and straight lines) from companies that dug the trenches and put the fibre in, or from companies offering lit or dark fibre in trenches someone else built for them.

Then again, they have little clue what the companies leasing the fibres actually do in terms of their underlying network topology, and what they (and their wholesale customers, reselling to other ISPs) do atop of that with the logical network topology.

From the outside, one only gets a blurry glance at the logical network topology of different ISPs from reverse DNS lookups on hop's IP addresses showing up in a traceroute, where ISPs sometimes encode site names or city names in the PTR record. The most accurate info in there might be that IP addresses show up which can be assigned to a well know internet exchange - which in turn might be spread across multiple datacenter sites around a single town with multi-kilometer distance.

Other than that, there might be geolocation databases of IP addresses and hints taken from the IP Registries in the Whois database - but again, that gives you just hints at where an intermediate network device might be. All those "graphical traceroute" tools are just based on information sources like these.

  • I was expecting that on ISP level, there wouldnt be much data - but i was less interested about which traffic light my data flows under, and more in the countrywide scale, so rather the cabling that was done by the country and not by specific ISPs (at least as far as i know), so e.g., does the data from Prague to Lissabon go through Switzerland or Germany, something like that - I cant think of a reason why submarine cables are mapped, and continental cables are not Commented Apr 17, 2019 at 10:49
  • In that case, the degree of accuracy provided by "graphical traceroute" tools might be good enough, if you combine that combinded with some good human assisted parsing of reverse DNS, which sometimes yields hints about geography ("NYC", "AMS", "ZRH" are pretty unambiguous), the whole thing enrichened by whois lookups or geolocation databases, and sanity-checked (with some inaccuracy) against the reported RoundTripTimes of the individual hops (for example:. there's no way a packet makes it form Europe to Australia and back in 100ms). Commented Apr 17, 2019 at 11:35
  • Yea, geoIP tracerouting is cool enough to play around (though i sadly didnt find a quick tool to trace from my own IP, only from other servers), well, i sent a mail to my local ISP, im just very curious how the cables are laid out, especially since some of the pipes in europe are a few hundred years old Commented Apr 17, 2019 at 13:31

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