(Source: http://aranin.ru/?p=527)

 Dune Efa (Petsh) is the highest dune in the Baltic States and Europe. Its height ranges from 61 to 64 meters. A pile of sand that had once been wandering (or nomadic) dune is named after Franz Eff - a man who was able to stop her.

Dune Inspector Wilhelm Franz Eff devoted more than 40 years of his life for the Curonian Spit. Here he died on September 16, 1904 in the village Rossitten (now Rybachy) and he was buried here. Over the past five centuries the wandering dunes were the main enemies for the inhabitants of the coastal towns and villages of the Curonian Spit. Subject to the power of the sea winds, the dunes are moving from the Baltic Sea to the Curonian Lagoon, to finish the way to the water. They simply crawl forward with a speed and focus of steamroller. If a village is met on the way so much the worse is for the village.

Sand penetrates into the cracks of houses, windows and doors, until it takes the whole house. People just have to move to a new location. Work on the Curonian Spit unfolded at the beginning of the XIX century. In accordance with the project of Titius, the foredune was banked on the coast: "brake earth mound" for sand, and right behind it a predune plain was made. Works on arrangement and securing the foredune along the seaside spit (which is more than 100 km) have been lasted for 100 years. It happened like this: first, the strengthening of such fences of sticks was constructed, which eventually were banked by sand. Then the next row of fence was erected on the top.

Once the height of the earth mound became appropriate, the fascines, square cells of brushwood, were arranged on top. The wooden stakes were piled in the squares joints by one meter depth, and grass was planted inside that grows well under the sea wind and hot sun, strongly bonding the soil by means of long roots. And pine trees were planted on the stopped sand, the roots of pine trees spread over the breadth and sprouted. In what connection is Franz Eff? Systematic afforestation was carried out under his leadership in 1880 that stopped the extension of wandering dune Petsh to the village Pillkoppen (Marine). Dune inspector Eff saved whole settlement and its contribution to the rescue of the Curonian Spit cannot be overestimated: at his presence the technique of   strengthening of dunes and woods landing was improved and perfected. Dune, stopped by Eff, retains its height, shape and location for more than a hundred years.