Pražský zlom, Natural monument in Hloubětín, Prague, Czech Republic

Pražský zlom is a protected natural monument in Hloubětín, Prague 14, preserving the only exposure of the Prague Fault, a major crustal dislocation. The outcrop shows Ordovician quartzites and shales, with the rock fractured into blocky ledges and steep faces above grassy ground and low shrubs.

The Prague Fault is a roughly 60 km long WSW–ENE crustal dislocation; at this site it is mostly a normal fault with the northwestern block downthrown, though some authors describe a more complex development with local inversion. The protected outcrop preserves Ordovician quartzites and shales, the only exposure of the fault, which is why the natural monument was declared.

The name refers to the Prague Fault, whose only exposed outcrop is protected here. The site lies in Hloubětín, Prague 14, and is managed by the Prague nature conservation agency; the rock face is kept clear of overgrowing vegetation so the Ordovician quartzites and shales stay visible.

The site is small and easy to reach on foot once you know its location. Since it is a protected natural area, visiting during daylight hours is recommended and sturdy footwear is helpful when exploring the exposed rocks.

The protected outcrop is the only place where the Prague Fault, a crustal dislocation running roughly west-southwest to east-northeast for about 60 km, can be seen at the surface. Most of the fault is vertical, but it is mainly a normal fault with the north-west block dropped down; some authors describe a more complex history with local inversion.