2008-05-27 54 -2
On 27 May 2008, the first day of the 30W Time Zone Rule, the geohash for Carlisle using the algorithm was along the River Wenning, just outside Wennington, at 54.125367°, -2.577111°, within walking distance of a train station.
Consensus so far seems to have put the meetup location on the near (road-) side of the river, not across the river, as the map says.
There was a stone structure in attendance. Was that built by a geohasher earlier in the day?
Adam Lindsay, around 4pm.