I assume that in its most basic form I could redo Dopplr of sorts by announcing travel plans in an OPML file, much like book lists or my rss subscriptions. Then it comes down to how to share such travel plans with a known and limited network only. (You don’t want to announce to just everyone when you won’t be home.)

The IndieWeb efforts concerning travel seem to focus on posting actual travel movements, like planned flights. A sort-of check-in style post. The socially shared Dopplr info was much simpler: a city and a set of dates. Because its purpose was aiding serendipitous meet-ups. Exact travel plans or exact location aren’t needed for it, just a way to flag paths more or less crossing to those involved.

Of course making such an OPML file currently is as easy as posting an empty file, as there’s no significant travel during the pandemic.

Theoretically I could use such an OPML file to announce several things:

• The various cities I consider as home turf, as they’re within easy reach in an hour.
• Selected cities I’m willing to travel to at short notice outside that hour travel time if there’s a good reason to.
  From where I am a visit to Antwerp, Brussels, Eindhoven would count in that category, or maybe on specific occasions Düsseldorf or Cologne.
• Upcoming travel plans, things like ‘Copenhagen, Denmark, 4th-7th September’ (actually a 2019 example)

Such a list would allow comparison with your list to see whether any of your travel plans match with my ‘home turf’ and destinations I’m willing to consider outside of it, whether any of your travel plans match with my travel plans, or whether any of my travel plans line up with your home turf and other relatively nearby destinations you’re willing to consider. Cities and countries are part of schema.org vocabularies and as such usable in OPML as data attributes.

I think there’s a space for location based services, such as Dopplr was, that don’t depend on or use maps, but provide location contextualized information that influences my actions, choices and my relationships to my networks (a quote from a 2012 blogpost on moving beyond the map).

Or this is just me applying my current opml hammer to anything that might be a nail 😀

I couldn’t resist making this mock-up mimicking the colorful Dopplr