Two of them were Brits, the third a Swede and having chatted for 15 minutes about Stonehenge the third chap - Eric - asked me if I'd ever heard of Ale's Stenar, a stone boat monument near Kåseberga in southern Sweden, and if I knew anything about its astronomical alignments.
I didn't - I'd vaguely heard of it but hadn't considered it in an archaeo-astronomical context.
Google Earth is my friend, so having found Ale's Stenar I plotted the long axis and discovered that it's aligned on winter solstice sunrise, full orb, over the sea horizon to the south east.
Not only that, but it's at the latitude where the summer and winter solstice sunrises and sunsets are all at 90° to each other, which is exceptional and wonderfully balanced.
What blew me away was the realisation that its outline is made up of 55 (or 56) stones (there's a suspicious gap on one side between S15 and S16), which is the same as the number of Aubrey Holes at Stonehenge.
Since one of the arguments levelled by archaeologists against the Aubrey Hole eclipse season predictor theory (Hawkins' and Hoyle's work) is:
"If 56 was a significant number, we'd see it used elsewhere - and we don't"
... then any instances of obviously solar aligned structures employing a 56-ness are useful counter-examples.
To date, I was only aware of two: Stonehenge and El Infiernito in Colombia. Now I can add a third.
Ale's Stenar - click above to see larger image