"This year, Slovenian volunteers will join millions of people cleaning up their own countries all across the world," Ecologists Without Borders said in a press release, adding that 150 countries will participate in the global campaign next Saturday.

About 70% of Slovenia's more than 200 municipalities will take part in the campaign, the organisers said at a press conference on Wednesday. Anybody can join the effort also by applying at ocistimo.si to get a free pair of gloves and a sack.

It seems that the people of Ljubljana will be the most active of all. In the capital, the project will involve 48 primary schools, 32 kindergartens and a number of secondary schools, not only on Saturday but also in the days before and after.

Those who do not want to collect garbage can help in compiling a register of illegal dump sites. Moreover, the campaign will also include tending to tree avenues, planting trees, painting park benches and sprucing up playgrounds.

In the first two campaigns in 2010 and 2012 a total of more than half a million people took part, collecting nearly 20,000 tonnes of waste. The figure will expectedly not go as high this year, as most of the waste collected will expectedly be packaging.

In 2010, Ecologists Without Borders were honoured by the then President Danilo Türk with the Order of Merit for organising what was the biggest environmental campaign in the history of the country, attracting more than 270,000 volunteers.

The number was even bigger two years later, when 289,000 people joined the effort. By then the campaign previously called Cleanup Slovenia in a Day became a part of the World Cleanup Day initiative.

The military and the police also participated in both previous campaigns, as did several other public services. The campaigns resulted in a registry of illegal dumps across the country, with volunteers reporting nearly 16,000 illegal dump sites.

Although this is only the third campaign by Ecologists Without Borders their efforts that started in 2010 have given rise to frequent cleanup campaigns which have been taking place across the country for years.