Originally Posted by RobJersey
Dane shows a perfect example of euro style.
Yes, it's a perfect example for a European style enclosure but not necessarily one for dart frogs. Those have - as Philsuma said - the sloped bottom for drainage.
Here's mine that was customed built for my frogs.
European style enclosures have mostly sliding doors, but there're also some with guillotine-style doors where you pull the glass plate in the front upwards to open it. Those are mostly for invertebrates.
And yes, they are also made entirely out of glass with mesh stripes in the front (that's the purpose of the ledge you're asking about) and in the top for ventilation. That causes the chimney effect that is also used with the Exo Terras.