Having been to both zoos, I think Prague definitely has the advantage here. Granted, 'Monsoon Forest' was closed when I went to Chester, and with my visit coming in the winter, the whole 'Islands' complex had a lot of immersion-breaking areas of sparsity, and the blatantly English surroundings made the themed elements seem even more obtrusive.
Prague's three absolute best exhibits (in my opinion) all count here, as do some of their biggest breeding triumphs, and there is lots else of serious quality throughout the zoo. Chester has perhaps the two best orangutan enclosures in Europe, a series of mammal enclosures in 'Islands' and their vitally prolific record with Babirusa, but in terms of overall novelty, creativity and quantity the Czech zoo is ahead.
Starting off with those three exhibits which I mentioned as being Prague's best...
Giant Salamander Pavilion / Velemlokarium:
A very simple but effective design that may be the best showcase of this fascinating species in the world. The Velemlokarium is a network of five very sizable aquaria, well-landscaped with rocks and dens for privacy, plus numerous further offshow tanks all allegedly connected by a water cascade. Two of these have a particularly interesting design where a pane of glass hidden just below the surface of the water gives the illusion of them being open-topped an unnervingly easy to fall into, while a third encourages you to climb in and look up at the salamanders, something that people of all ages can do. For half the day, the Pavilion is kept in nocturnal conditions for optimal activity, and policed by staff to prevent loud noises or photography; the resulting darkness and silence only enhances the oddity of these truly giant salamanders (and some of Prague's specimens are especially giant!).
With vivariums for two further rarities (Impressed Tortoise and Mangshan Pitviper) also present.
Gharial Pavilion / Chambal:
Another example of Prague taking a very simple and ubiquitously used idea and turning it up to eleven to enormous success. At the end of the day, Chambal is a big indoor pool with crocodiles. But the presence of 6 crocs, the fact that they are of a scarcely kept species (Gharials), and all six of them are enormous specimens makes it a little more dramatic. Then there are the inhabitants mixed with the crocodiles: huge and colourful schools of various fish including Giant Danios, and four species of turtles, all relatively rare in captivity, starring the huge, critically endangered Northern Batagurs who often follow the crocodiles about in a tremendously entertaining display. And if that isn't interesting enough, there is also a terrestrial species living with the Gharials on land, the Indian Star Tortoise!
Design-wise, the pool is simple. Very large, very deep, with three separate banks for resting, but just as nice is the flooded bank allowing the animals to lie down and rest while still being partially in the water.
There is also a very large outdoor pool, but I don't think the Gharials have access to it anymore. On my visit it was home with European Pond Turtles who in theory could be mixed with the crocs just as the Asian turtles are, but I don't think so. I've been told in the post on this forum that the long-term plan is potentially to make this indoors and an extension of the exisiting pool. Just in case it is still in use, I've attached a photo.
Rock Outcrop:
I imagine that most enthusiasts are familiar with these exhibits regardless of whether or not they've been to Prague. Two of Prague's huge cliffiside goat exhibits, providing mountain-dwelling bovids with a near-vertical rock slope, house Asian species: West Caucasian Tur and Himalayan Tahr. Both of these enclosures are mind-blowingly good. I won't go into too much detail as the photos speak for themselves.
But it isn't just goats. There are also red pandas and a huge aviary for Cinereous Vultures and Booted Eagles. Chester also has a huge Cinereous Vulture aviary, but Prague's is slightly bigger by area and quite a bit bigger by height (though the latter is of course purely guesswork as it can't be measured with Google Maps

).
Now moving onto what may well be ZooChat's favourite Prague exhibit, and even if I don't quite love it as much as other enthusiasts do, it's impossible to deny its excellence.
Sichuan Pavilion:
Again, simple but excellent. A fairly large indoor walkthrough aviary with dense foliage and a good mix of lively birds. The added layer of excellence comes from the fact that its not tropical, but a temperate forest-based aviary for birds of the Sichuan province in western China, and barring a few random, slightly immersion-breaking palm trees, the vegetation reflects this. There are plenty of rarities, with the only Scaly and Barred Laughingthrush in Europe to name just two.
So post #40 in
this thread for a species list.
That's all that I have time to do for the time being but I will definitely come back later and cover the rest of the zoo if nobody else has beaten me to it.
