DMI ocean observations (Denmark)

What it is: Sea-level observations at 10-minute intervals from Danish stations, with a historical archive, published through DMI's open-data API.
Publisher: DMI (Danish Meteorological Institute).
What OTC takes: Gauge records that OTC fits. No harmonic constants are published. DMI's own tide predictions can serve as a cross-check. Inner Danish waters have very small tides, so the fits are most useful on the North Sea and Wadden Sea coast.
Licence: CC BY 4.0, as stated in DMI's terms for its free data.
Attribution line OTC uses: “Contains data from DMI (Danish Meteorological Institute), CC BY 4.0.”
Access and watching: Keyless OGC API Features (version 2). DMI limits requests per IP address. A weekly fetch of new records.
Coverage: The station list returned 201 stations: the Danish coast, and some in Greenland and the Faroe Islands.
Rank: Gauge fit.