It's a window opening in a cell in Kilmainham Gaol in Dublin, but I like the shape and the placement in the frame.
A simple arch is always interesting. This one is from Ravenna, Italy, but I always like arches.
These rocks are a fascinating - they're from The Giant's Causeway in Northern Ireland. This could be a great motif, but might be too time consuming for the workshop.
I love the positive and negative possibilities in this - and would like to design something that looked like it had lights in some of the windows. I'll post more as the process goes along.