I like the old-school green painted angle iron used in this enclosure.Characteristic of many of the most successful lion / tiger enclosures of the recent past.In many ways the wave of enclosures that came after these have actually been a step backwards.
Chester's lion enclosure was the first in the world to use chain-link fencing; it met with significant opposition and over half the board of directors threatened to resign because of it. George Mottershead accepted their resignations, and built the enclosure anyway.
The enclosure is much the same today, although I don't think the wire was supposed to be the subject of this photograph.