The mystery of the new island in Cardigan Bay can finally be revealed as the work of the team behind ABERETWM, a site-responsive performance to celebrate the 50th anniversary of Aberystwyth Arts Centre.

The 'appearance' of the island caused a stir on Wednesday and Thursday, and the appearance of viewfinders on the promenade attracted the attention of locals and visitors alike. Although not visible to the naked eye, the 'island' can be seen through the viewfinders.

The seafront installation is part of the artist Marc Rees' work to celebrate the arts centre by subverting an ancient local myth and reimagining it as a cross-artform site-responsive performance.

As well as the 'island', tents have pitched up in the castle, and last night lights in the sky delivered a coded message.

Today further sightings of the island can be seen through the viewfinders until 10pm tonight.

The encampment at the castle also continues with a sound. light and multi-sensory installation in the grounds from 3pm until late. There will be another illumination of the sky from 10pm-midnight. A procession has also been advertised for today, which can be seen on Aberystwyth Arts Centre's Facebook page.

The viewfinders will remain on the seafront tomorrow (Saturday, 8am-10pm), and the lights and procession will also be shown again.

Enjoying the viewfinders yesterday were former Aberystwyth University student Rose Grifftiths and her boyfriend, Jason Jones.

Rose Griffiths and Jason Jones
Rose Griffiths and Jason Jones enjoyed looking at the 'island' (Julie McNicholls Vale)

Rose, who got an English Literature degree and a Masters in Literary Studies at Aberystwyth said that although she wasn't sure what was going on at the seafront, she was intrigued. She also praised the arts centre, saying: "It has always been great. I've seen a lot of shows there."

Jason was equally intrigued, and added: "I work in the arts in Worcestershire so it's nice to engage with art in a different place."

On Sunday, ABERETWM finishes with Washed Up, when more about the mystery on the seafront will be revealed (3.30pm-4.30pm, caption and audio described) and the arts centre takeover. A number of events will take place at Aberystwyth Arts Centre from 12pm-10pm. There will be talks, films, exhibitions, performances, installations, a projection on the building and a birthday party. From 7pm-8pm there will be a concert in the Great Hall where a new libretto, written by Welsh poet Mererid Hopwood and accompanied by a brand new concerto for multiple soloists by Claire Victoria Roberts, will be performed by a variety of local groups including Philomusica, the choir of Ceredigion Music Service, the Elizabethan Madrigal Singers, Cerys Havanna and Owen Shiers. No tickets are required and the concert will be captioned and have audio description.

So pop down to the seafront, over to the castle and up to the arts centre to celebrate its 50th anniversary.