Zelenci is one of the most photogenic natural springs in the Julian Alps - an emerald-green lake that marks the source of the Sava Dolinka, Slovenia's longest river. Water emerges here from depths of up to 2 metres, creating an intensely green colour that gave the spring its name.

This is a place that delights in every season - lush and green in summer with blooming marsh plants, and strikingly contrasted against the snow-capped Karavanke peaks in winter. At the bottom of the lake lies porous lake chalk through which groundwater constantly bubbles up in small 'volcanoes', a phenomenon unique in Slovenia. The water maintains a constant temperature of around 5-6°C. A walk along the wooden boardwalks and paths around the reserve is an easy, relaxing outing suitable for the whole family, and a perfect complement to hikes around Kranjska Gora.

How to get there

• Kranjska Gora — parking near the reserve, about 10-15 minutes on foot, easy route
• Podkoren — short walk along the Sava Dolinka river, easy route

Practical information

• Protected as a nature reserve since 1992
• The reserve covers an area of 14 hectares
• Information boards and a viewing bridge with a tower are set along the paths
• Home to endangered species such as the smooth snake, common European adder and brown trout - please stay on the marked paths

Legend has it that the mesmerising green of the water and surrounding wetlands inspired the painter Ladislau Bencsh, while British naturalist Sir Humphry Davy wrote that he knew nothing more beautiful in all of Europe than the Sava valley.