Pilis-nyergi-víznyelőbarlang is a small but fascinating sinkhole cave tucked away in the Pilis Mountains. It is a place for those drawn to hidden natural wonders and decades of caving history rather than sweeping panoramic views.

The cave lies near a hiking trail junction in the Pilis-nyereg saddle, between the peaks of Nagy-Szoplak and Fekete-hegy. The surrounding forest, part of the Duna-Ipoly National Park, offers a quiet, shaded atmosphere in summer, vivid colors in autumn, and a peaceful stillness in winter. The cave itself functions as a seasonal sinkhole, swallowing surface water during wetter periods and channeling it into the karst below.

• Starting point: the trail junction at Pilis-nyereg saddle — moderate difficulty, reachable on foot from villages at the base of the Pilis massif
• The cave's location is marked on some hiking maps of the area

• The cave is currently closed to visitors due to a collapse in its passages
• Access always required special permission and basic caving equipment
• It has held special protected status in Hungary since 2006

First explored in 1961 by cavers from Dorog, the cave features delicate flowstone formations and has yielded surprising finds, including fossilized horse (Equus caballus) bones and fragments of Roman-era pottery, hinting at ancient human activity in the area.