Perito Moreno Deep Dive
Perito Moreno is the headline glacier of South America. Around 257 km2 in area, with a calving face roughly 5 km wide and 70 m above the waterline, it draws over half a million visitors a year and is one of the few large temperate glaciers in the world that has held steady or even slightly advanced in recent decades.
Geography
The glacier descends from the Southern Patagonian Ice Field across the border in Chile to Lago Argentino on the Argentine side. Its characteristic behavior is to push across the Magallanes peninsula and seal off the Brazo Rico bay from the main lake. Water levels in the sealed arm rise — sometimes by 30 metres above the lake — until the pressure differential ruptures the ice dam in a spectacular collapse.
Calving cycles and dam breaks
Major dam-break events have been documented since 1917. They are irregular — the gaps between them have varied from a few months to over a decade. The most recent major rupture was in March 2023. Day-to-day calving is constant: a piece falls from the face roughly every few minutes during warm afternoons.
Visiting
El Calafate is the only practical base. Buses leave the town for the park entrance (80 km, paved road) several times a day in season. The park entrance fee is paid at the gate in Argentine pesos. Once at the glacier:
- Walkway visit (free with park entry). Boardwalks built into the forest above the south arm. Best general view; allow 2-3 hours.
- Boat tour (extra). Hielo y Aventura, Solo Patagonia and others run trips along the south face — closer view, often with calving.
- Mini-trekking (extra). 90-minute guided crampon walk on the lower clean ice; year-round.
- Big Ice (extra). Full-day guided ice walk further onto the glacier; serious fitness required.
When to go
Year-round. November-December and March give the best weather/crowd balance. The walkways are open year-round, including winter when low sun light creates the deepest blue-ice photography.
Why it stays steady
The dominant theory is that heavy winter snowfall on the ice field compensates for summer melt. Some studies also suggest the ice's bed geometry — a deep basin upstream of the snout — protects the calving face from rapid retreat. Either way, Perito Moreno remains one of the few glaciers visitors today can see and assume will look similar in another decade.
Keep exploring
Find Perito Moreno on the interactive map — including the proximity boundaries, ferry departure points and webcam links for remote viewing before you book.