Remember the mural that Joe Caslin painted in Dublin's city centre to raise awareness about Ireland's referendum on same-sex marriage? The artist is back again, but this time the subjects are women and the location has moved to the Irish countryside.

Same-sex marriage is not yet legal in Ireland, although a referendum is being held this Friday to determine whether or not gay couples should be allowed to tie the knot. Early polls suggest that Ireland will vote overwhelmingly in favour of legalising same-sex marriage, but us Brits know by now not to trust such predictions as far as you can chuck 'em.

Caslin works predominantly in large, public spaces to ensure that his message gets noticed. Whereas the two men hugging in "The Claddagh Embrace" took pride of place in the heart of Dublin's city centre, this unnamed artwork is out in the countryside on Medieval Caherkinmonwee Castle in County Galway. The location may be more remote but the message is no less potent, particularly this close to the referendum.

Caslin believes that the switch from city to countryside will help him to connect with people who may take a more conservative approach at the referendum, with Caslin working on the assumption that those living in rural areas hold more traditional attitudes than city-dwellers. That said, some conservative Dublin residents made a failed attempt to have "The Claddagh Embrace" removed as "it constituted a breach of the planning act".

"It was very targeted that this work would be extremely rural," Caslin told Dazed. "The referendum will carry in urban locations. The pace of life is different, much quicker – change and differences in lifestyle are far more readily accepted. Things are much more traditional in these places. I didn't want to have a referendum in one city, but for every person on the island."

As was the case with "The Claddagh Embrace", the unnamed mural is modelled on a photograph taken by Irish photographer Sean Jackson. Both images share an atmosphere of stillness and comfort – they're beautiful murals that convey an instant sense of love, a feeling that Caslin says is essential to understanding this referendum.

"Imagine this is your life," says Caslin."You're out there canvassing. It's about beliefs, about morals, about something close to your soul. This is a life changing referendum. It's incredibly important and I know what I'm doing is right."

The Irish referendum on same-sex marriage takes place this Friday.