The Slovenian National Drama Theatre, Ljubljana's main theatre house, will undergo a thorough renovation starting this month with preliminary archaeological works on the site. Both the main early 20th century building and the two 1960s extensions will be renovated.

The project, valued at nearly €60 million, involves a complete rebuilding of both the large and the small stage, construction of two rehearsal stages, replacement of all fixtures and fittings, and new lighting and stage technology.

The building is no longer fit to serve as a modern theatre house and some of the existing technology "belongs in a museum rather than in a modern theatre house", theatre director Vesna Jurca Tadel said on 5 July.

Renovation has been planned for more than a decade but plans were accelerated last year, when a heavy storm flooded large parts of the building, causing serious damage.

As a result, the refurbishment was placed on a list of projects of national importance and provided state financing.

Chief architect Matija Bevk of the Bevk Perović architecture bureau said the idea is to create a "modern national theatre" by preserving and restoring the historical building while also revitalising the area around the theatre.

The archaeological digging will start in the second half of July and is expected to take about six months. Since the building is right of the centre of the Ancient city of Emona, archaeologists expect to dig up finds from the Roman era and later historical periods.

The main construction work will be conducted through 2024. The entire next season will still be performed in the existing building, whereupon the theatre will temporarily move to the Litostroj industrial zone.