By combining a regular run with the ParkRun and an extra loop home I managed to cobble together a half-marathon. It did include 16 minutes in 3 breaks between the segments so it wasn't continuous, but very nearly so. At least that is a 'target' beaten and by no means was it an easy course as it included 438m of ascent, a snow covered 500m and a sub-25 minute 5k near the end. I'm content with under 2 hours (moving time) for that (note that it is TWICE world record time).
Significantly the sun was out and I ran the 5k without a jacket! Perhaps it really is spring now?