On Saturday, 23 March 2013, from 8.30 until 9.30pm the City of Ljubljana joined Earth Hour, the world’s largest environmental project.

We were stargazing from the darkened Ljubljana Castle; we taked a stroll through the darkened Plečnik Arcades of Ljubljana central market, and the darkened Plečnik’s Žale cemetery. Some public enterprises and public institutions were turning their lights off as well.

The main event of Ljubljana's Earth Hour were stargazing from Ljubljana Castle, organized by Dark Sky Slovenia. Ljubljana Castle is one of the most visited tourist destinations in Slovenia.

The cultural monument, Plečnik’s Žale cemetery - All Saint's Garden, received the European Heritage Label in 2007. This exceedingly renowned award is presented by the Committee for European Heritage, composed of the Ministers of Culture and Heritage from Member States of the European Union who confirm proposals from the National Committees for the European Heritage Label in accordance with strict criteria and rules and through consensus.

The Plečnik’s Arcade cultural monument is the work of famous architect Jože Plečnik, who besides Ljubljana also practised in Vienna, Prague, and Belgrade.