trailmarkNational Parks passport

Privacy Policy — Trailmark

Last updated 6 August 2026. Trailmark is operated by the AI Agency.

The short version

There is no account, so we never ask for your name, your email, or anything else that identifies you. Your saved parks live in your own browser. When you open the map, the list of park slugs you have tapped is sent to our server so we can estimate your percentile and count per-park popularity — and nothing is attached to it: no identifier, no account, no session, nothing that could point back at you.

What we collect

Exactly one request carries anything about your collection. When you open the map, the app sends { "visited": ["acadia", "zion", "denali", …] } to POST /api/tallythe full list of park slugs you have tapped, and nothing else. (The app also calls GET /api/health on load, which sends nothing and returns a status check.)

On our side that becomes two things, stored in a single DynamoDB table:

  • A collection-size histogram (item id="histo"): a buckets map keyed by collection size — one counter for each size from 1 to 63 — plus a total count of all collections ever tallied. This is what produces the "top X%" percentile on your map. It carries no identifier, no IP address, and no session id. Your collection size is indistinguishable from anyone else’s with the same size.
  • Per-park popularity counters (items id="park#acadia", id="park#zion", and so on for each park in your list): each holds a single count number that increases by one every time that park appears in any collection. These feed the "Most visited parks" ranking. Like the histogram, a counter carries no identifier and no record of who contributed to it.

Your device’s IP address reaches our servers as part of any web request, as it must for a page to be delivered at all. We do not store it and we never record it alongside the tally.

What stays on your device

One entry in your browser’s localStorage, on this device only. It is not a cookie, and it is never transmitted anywhere except as described above:

  • trailmark.v1{ "visited": ["acadia", "zion", …], "updatedAt": "2026-08-06T…" }: the list of park slugs you have tapped, and when you last changed it.

The growing-link in your address bar (?c=<base64url>) encodes the same visited set as a compact 63-bit mask — one bit per park in a fixed, append-only order — so you can share your exact collection by copying the URL. It carries no identifier and structurally cannot carry text. Anyone you send the link to can see your collection map, so share it where you would like it seen.

Because your parks live only in your browser, clearing this site’s data erases your collection, and we have no copy to restore it from.

Advertising & cookies

We use Google AdSense to show ads. Google and its partners use cookies (including the DoubleClick DART cookie) to serve ads based on your visits to this and other sites. You can opt out of personalized advertising via Google Ads Settings, or opt out of third-party vendor cookies at aboutads.info/choices. We ask for your consent before loading ad cookies.

Your rights (GDPR / CCPA)

You can accept or reject cookies at any time, and you can clear them in your browser. Clearing your browser data also erases your saved map on that device. We do not sell personal information.

Contact & data rights

To exercise your GDPR/CCPA rights, opt out of personalised ads, or ask a privacy question, email auto-ai-agency@quantum-solutions.hr. We respond to verified requests within 30 days.

Back to the map