The maar is approximately 20,000 to 30,000 years old.
The Strohner Määrchen is considered a 'dry maar' that developed into a bog due to sediment accumulation.
The water level remains relatively constant because it is primarily fed by groundwater and precipitation rather than streams.
The steep funnel shape of the crater is exceptionally well-preserved compared to other maars in the region.
The name 'Pulvermaar' is rumored to stem from the loud explosion sound produced during its volcanic formation, often compared to gunpowder.
Pulvermaar is one of the deepest and most circular volcanic crater lakes in the Eifel region of Germany. Formed by a phreatomagmatic eruption, the lake reaches a depth of approximately 74 meters. It is surrounded by a dense forest canopy and the volcanic ridge known as the Römerberg. Adjacent to the main maar is the Strohner Määrchen, a smaller, shallower maar that has partially silted up to form a moorland habitat. The site is a protected natural monument and part of the Vulkaneifel UNESCO Global Geopark. Swimming is permitted in designated areas during the summer months. Visitors can walk the complete perimeter of the lake via a well-maintained forest trail. The lake's water is characterized by low nutrient levels and high transparency due to its depth and origin.
The high vantage point on the western edge of the Römerberg provides a complete circular view of the lake.
Bring sturdy footwear if planning to hike the full trail around the crater rim.
Check for blue-green algae warnings at the information boards before swimming.
Carry insect repellent, especially when visiting the boggy Strohner Määrchen area.
Attempting to swim outside the designated lido area, as the steep crater walls make entry and exit dangerous elsewhere.
Swimming facilities and kiosks are seasonal, typically operating only from late spring through early autumn.
Stay on marked trails to protect the fragile volcanic soil and moor vegetation; do not feed waterfowl.
