Explore some of Wales' most remarkable historic places for free as Cadw's Open Doors festival returns

This September visitors are being invited to step behind closed doors, uncover hidden stories and explore some of Wales' most remarkable historic places for free as Cadw's Open Doors festival returns for 2026.

Following a busy summer of events, Open Doors will offer free entry to hundreds of historic locations across Wales, providing a unique opportunity to discover everything from iconic landmarks to secret gems that are rarely open to the public.

From abbeys and castles to Roman forts and Victorian style prisons, there’s a huge variety of different locations taking part.

Funded and organised by Cadw, the popular Open Doors festival is Wales’ contribution to the European Heritage Days initiative, dedicated to showcasing the rich tapestry of cultures across the continent.

In Wales, it opens a gateway for visitors of all ages to step into the past, immerse themselves in the nation’s dynamic heritage, and uncover the compelling stories that have helped shape its identity.

Dr Ffion Reynolds, Cadw’s Senior Heritage Events and Arts Manager, said: “Open Doors is a fantastic opportunity for people to explore the extraordinary heritage on their doorstep and discover places they may have never visited before.

"Whether you're interested in castles, archaeology, industry, religion, literature or local history, there is something for everyone. By opening these places free of charge, we're helping more people connect with the stories, people and landscapes that have shaped Wales.

"This year's programme includes many unique experiences, from behind-the-scenes access and guided tours to opportunities to visit places that are rarely open to the public. We're particularly excited to be able to welcome visitors to parts of the historic Mynachlog Fawr farmstead at Strata Florida as part of this year's festival."

In Powys some of the festival's highlights include Powis Castle and Gardens in Welshpool open on September 12 and 13 from 10am until 5pm.

Set amid lush greenery with sweeping views of the Severn Valley, Powis Castle is renowned for its grand interiors and world-famous terraced gardens.

The castle is adorned with world-class paintings and decorative fabrics spanning the Elizabethan to Edwardian periods.

During Open Doors, visitors can explore both the castle and its magnificent gardens free of charge.

Brecon Royal Observer Corps Monitoring Post in Brecon is open on September 12 from 11am until 4pm.

Climb 15 feet underground and discover life on the frontline of the Cold War at the Brecon ROC Nuclear Monitoring Post.

Restored to its original operational condition, the bunker offers a rare glimpse into the role played by Royal Observer Corps volunteers who monitored the threat of nuclear attack across the UK. Visitors can explore the fully equipped underground post and hear first-hand stories from former ROC personnel about this fascinating chapter of modern history.

The Old School, Whitton is open throughout September on Mondays and Tuesdays from 11am until 5pm and on Sundays from 1pm until 5pm.

Visit the Museum of Welsh Textiles to see displays of Welsh costume, blanket quilts and vernacular items reflecting the lives of traditional weavers and the communities they served.

Located in an old school building, the museum also cares for the safeguarding of endangered crafts and teach crafts like Welsh quilting and smocking.

Newtown Library in Newtown will be open on September 8 from 10am until 3pm.

For Open Doors, visitors can explore the rich history of Montgomeryshire with guided access to historic newspapers, maps, books and community publications, while discovering the resources available for local history and family history research.

Powys Archives in Llandrindod Wells will be open on September 26 from 10am until 4pm

Discover centuries of local history at Powys Archives, home to records spanning Montgomeryshire, Radnorshire and Breconshire from the 14th century to the present day.

As part of Open Doors, learn more about the project uncovering the work of Powys photographer Ernie Husson, explore the results of an innovative 3D model printing initiative and find out how archives help preserve the stories of local communities for future generations.

Welshpool and Llanfair Light Railway in Welshpool will be open on September 12 and 13 from 10am until 4pm.

Discover the story of one of Wales' most distinctive narrow-gauge railways at the Welshpool and Llanfair Light Railway. For Open Doors, visitors can attend talks on the history of the line and its locomotives before joining guided walking tours exploring the railway's original route through Welshpool.

Visitors are advised to check individual event listings as booking requirements vary between locations.

Full details of all participating venues, dates and ticketing information can be found on Cadw’s Open Doors website here: https://cadw.gov.wales/visit/whats-on/open-doors-events