Historic buildings, landscapes and cultural sites across Northern Ireland will open for free during European Heritage Open Days on September 12 and 13. The annual programme includes places that are not normally accessible to the public as well as special tours and activities at established attractions.

This year's theme is Heritage at Risk: Revive, Resist, Reimagine. Events will examine how buildings, traditions and landscapes can be protected, adapted and brought back into use when they face pressure from deterioration, changing needs or environmental conditions.

The programme was launched at Coleraine Town Hall, one of the venues involved in the weekend. Participating sites extend across all council areas and range from civic buildings and places of worship to industrial heritage, gardens and archaeological locations.

Admission to registered Open Days events is free, although some tours and activities require advance booking because capacity is limited. Opening hours also vary between Saturday and Sunday, so visitors should check the individual listing before making a journey.

Organisers have published the programme online with filters for location, date and type of event. Accessibility information and booking instructions are included where they have been supplied by the venue, and late changes can also be posted on the listing.

The weekend forms part of a Europe-wide heritage initiative intended to widen access and encourage people to explore the history of their own area. Visitors are advised to plan a route in advance where they hope to attend several timed events.