Groapa Ruginoasa - Valea Seacă

Groapa Ruginoasă - Valea Seacă is a nationally protected area (IUCN Category III — a natural geological reserve and natural monument), located in the south-eastern part of Bihor County, on the northern branch of the Munții Bihorului range, part of the Munții Apuseni. It lies at an altitude of approximately 1,373 m, between Vârful La Morminți (1,430 m) and Vârful Țapul (1,475 m), on the territory of the commune of Pietroasa, within Parcul Natural Apuseni. It was declared a protected area under Law no. 5 of 6 March 2000, covering an area of 20.40 hectares. The geological phenomenon is spectacular: a massive gully with a diameter of over 600 m and a depth of over 100 m, formed through torrential erosion (gullying) of deposits of quartzite, sandstone and red clays. The erosion process has exposed layers of reddish-violet quartzite which, contrasting with the yellow-orange sand, give the area the appearance of an explosion of colour — described vividly by visitors as "ketchup and mustard". The sloping walls and sharp, blade-like ridges converge toward the centre of the gully, where the streamlet known as Valea Seacă originates — the source of an extremely difficult canyon accessible only to climbers due to its large drops. The volume of material eroded over time is estimated at approximately 7 million cubic metres. Erosion remains active today — the gully increases in size every year, swallowing the trees along its edges. A particular phenomenon observed here is that water laden with sand has cut through massive tree trunks by erosion, much like a saw blade. The eroded material, carried downstream by flash floods, gives its name to the stream into which it flows — Galbena. Access is from the Vârtop resort, via DN75 toward Ștei, where an information panel and a car park mark the start of the trail. The path, marked with a yellow stripe, ascends through forest with steps and handrails in the more difficult sections, reaching the rim of the canyon in approximately 30–50 minutes (1 km, with an elevation gain of 150 m). Signs warn that the edge may collapse.