Questions from the Hillside

Q: Why is Lake Gjende emerald green while Lake Bessvatnet right above it is deep cobalt blue?

When you stand on the Besseggen ridge, you see two lakes separated by a thin rock threshold. Bessvatnet is fed solely by rain and snowmelt, making its water crystal clear and deep blue-violet. Gjende, sitting 400 metres lower, receives heavy glacial meltwater from the Memurubreene glaciers via the Muru river. That meltwater carries fine suspended silt (rock flour) that scatters green wavelengths of sunlight.

Q: Can I walk onto a Norwegian glacier tongue if it looks flat and snow-free?

No. Even bare summer ice has deep crevasses, slippery water-worn surfaces leading into vertical moulins, and unstable calving margins. Walking on any glacier requires glacier crampons, an ice axe, a harness, a rope team, and training or a certified Norsk Fjellsportforum guide.

Q: What are the bright yellow-green spots covering boulders on high plateaus?

Those are crustose map lichens (primarily Rhizocarpon geographicum). They grow extremely slowly—often only 0.2 to 0.5 millimetres per year in cold alpine zones—and prefer acidic, silica-rich rocks like granite, gneiss, quartzite, and gabbro.

Q: Why do Norwegian mountains have flat plateau tops instead of sharp peaks everywhere?

Before the Quaternary ice ages, Norway was worn down into a gently undulating plain near sea level, then uplifted tectonically during the Cenozoic. Subsequent glaciers carved deep U-shaped valleys and cirques into the edges of this uplifted surface, leaving remnants of the ancient paleic plain intact on plateaus like Hardangervidda, Finnmarksvidda, and Sognefjellet.

1. Why is Lake Gjende emerald green while Lake Bessvatnet right above it is deep cobalt blue? −

Standing on the Besseggen ridge gives you a textbook demonstration of glacial sediment transport. Bessvatnet (1,373 m) is fed purely by local snowmelt and rain; with almost no suspended mineral particles, light penetrates deeply and only short blue wavelengths scatter back. Gjende (984 m) receives the turbid Muru river draining the Memurubreene glaciers. Millions of tonnes of microscopic rock flour remain suspended in Gjende’s water column, reflecting green and turquoise light.

2. Can I walk onto a Norwegian glacier tongue if it looks flat and snow-free? +

Never step onto glacier ice without proper glacier equipment (crampons, ice axe, harness, rope) and training or a certified guide (Norsk Fjellsportforum). Even bare blue ice on a gentle slope is slick enough to launch an unstoppable slide into a crevasse or vertical meltwater shaft (moulin), and the lower snout margin is prone to sudden slab collapse.

3. What are the bright yellow-green spots covering boulders on high plateaus? +

Those are crustose map lichens, primarily Rhizocarpon geographicum. Each yellow-green thallus is bordered by a thin black fungal prothallus, so when colonies meet they resemble countries on an old atlas. Because they grow very slowly (often 0.2–0.5 mm per year in continental alpine areas), geomorphologists measure the largest circular lichens on moraine boulders to estimate when the ice retreated—a technique called lichenometry.

4. Why do many Norwegian mountains have flat plateau tops instead of sharp peaks everywhere? +

Norway’s topography preserves an ancient pre-glacial landscape called the Paleic surface. Tens of millions of years ago, weathering wore Scandinavia down to a low, rolling plain. When the crust uplifted during the Cenozoic Era, rivers and later Quaternary glaciers cut deep valleys from the coast inward, but left wide interior uplands—such as Hardangervidda, Valdresflye, and Dovrefjell—as high, undulating plateaus.

5. What do the red 'T' paint marks on cairns signify, and when are trails snow-free? +

The red ‘T’ painted on rock cairns (varder) marks summer walking routes maintained by the Norwegian Trekking Association (DNT). Note that in high mountain areas above 1,100 metres, winter snowpack frequently lingers until late June or mid-July, obscuring painted rocks and summer footbridges. The prime snow-free geological observation window runs from mid-July through late September.

6. May I collect rock specimens or fossils in Norwegian national parks? +

Inside protected areas, geotopes, and national parks (such as Jotunheimen, Rondane, Dovrefjell-Sunndalsfjella, and Jostedalsbreen), hammering bedrock or removing rare minerals and fossils is prohibited so that key geological exposures remain intact for everyone. We encourage documenting structures with a macro lens, a scale ruler, and written field notes instead.

7. How does Norway’s Right to Roam (Allemannsretten) apply to photographers camping in the fells? +

Under the Outdoor Recreation Act (Friluftsloven), you may pitch a tent for up to two nights on uncultivated mountain land (utmark) at least 150 metres from the nearest inhabited house or cabin—and in high mountains remote from settlements, even longer. However, fragile alpine lichen mats take decades to recover from campfires or rock rearranging; always use established tent pitches when possible and never build new decorative rock cairns.

8. Why is building new stone cairns strongly discouraged in the mountains? +

Official navigation cairns have saved lives in dense mountain fog for centuries. When visitors stack decorative rock piles off-trail for photographs, they create false trail markers that can lead tired walkers toward cliff edges in whiteout conditions, while also disturbing spider and insect habitats beneath settled stones.

Questions from the hillside