Wielki Staw Polski — the Great Polish Lake — is the largest and deepest lake in the entire Tatra Mountains, sitting at 1665 m above sea level in the stunning Valley of Five Polish Lakes. Its emerald-green water plunges to a depth of over 80 metres, making it one of the deepest lakes in Poland and an absolutely unmissable stop on any Tatra hiking itinerary.

The lake is framed by steep rocky slopes, low-creeping pine scrub slowly reclaiming ground lost to centuries of mountain grazing, and the constant murmur of the Roztoka stream that drains its waters down to a spectacular waterfall — the Siklawa. In summer the vivid green surface mirrors the surrounding peaks; in autumn golden hues wash over the valley; in early spring the lake lingers under ice and snow far longer than the trails below. Arriving at dawn rewards you with mist drifting across the water and near-perfect solitude.

• Morskie Oko lake (Palenica Białczańska car park) — blue trail, approx. 2 h 10 min, moderate
• Wodogrzmoty Mickiewicza (road to Morskie Oko) — green trail via Roztoka Valley, approx. 2 h 05 min, moderate
• From the lake, the blue trail continues to Zawrat Pass — approx. 1 h 30 min, demanding

• The lake lies within Tatra National Park — an entry fee applies.
• Swimming and fishing are strictly prohibited.
• Trails may be closed in winter and early spring due to avalanche risk — always check TOPR (Mountain Rescue) bulletins before heading out.

Old Tatra mountaineers used to say that St Mary's Basilica in Kraków — tower and all — could be submerged in the lake with only the tip of the roof breaking the surface. A little more recently, in May 1952, a bear that fell through the melting ice was recovered and eventually preserved for the Tatra Museum collection.