Den: the lair of a wild animal; a place where people meet in secret
Mark: Place a symbol on, denoting position

Playing with variations of syllable counts and repetitions, like the Rondelet, Termelay, etc. This one has 14 line stanzas, with syllable counts of 6/6/6/12/12/12/6/6/12/12/12/6/6/6. The syllable count is designed so different meter can be used, if found useful.
The first 3 lines of each stanza repeat as the end 3. The middle two lines act as a repeat through all three stanzas. May be rhymed or unrhymed, be a set meter or not.
The 12-syllable lines must be a fixed meter or rhythm. I have chosen anapestic tetrameter, but iambic hexameter would work well.

The town of Denmark lies on the south coast of Western Australia. Greens Pool and Elephant Rocks lie about 18km west. We visited in the summer of 2013, when the daytime temperature rarely dropped below 40⁰C. Between Elephant Rocks and Denmark we spotted the eyrie of Of what was probably a sea eagle and the bird itself in flight. Not being close enough for a good view, and not being a bird expert, it could have been a different type of raptor.

I misremebered the name of the town, so my original notes labeled it as Denhaven, with questions like: Who finds haven here? Who lives in a den?