"Industrial areas are at a huge risk of being neglected in the process of restructuring of companies," Sonja Ifko of the Faculty of Architecture told a press conference ahead of International Day for Monuments and Sites.

However, some companies have recognised the value of their heritage and have made an effort to preserve it and present it to the public.

Tomorrow, visitors will have an opportunity to take a peak in the development of brewer Pivovarna Union at the Brewery Museum in Ljubljana, the railways history at the Railways Museum and the renovated Old City Power Plant.

The functioning of a hydro power plant will be presented at the museum Hydro Power Plant Fala, the oldest Slovenian hydro power plant on the Drava river, operating since 1918.

Ifko also highlighted the Museum of Post and Telecommunications at Polhov Gradec Castle just outside Ljubljana, the Coal-mining Museum in Velenje and the UNESCO-listed Idrija Mercury Mine.

The museums will be open admission-free between 10 AM and noon on Saturday, while guided tours will be available at 11 AM.