Large outdoor enclosure you`ve got to be joking the whole of the House and outdoor enclosures would fit into the area taken up by just 2 of Twycross Lemur exhibit and thats not the biggest area!
I only just saw this picture, I went to Noah's Ark last week and the indoor areas have changed... They now have small places where the primates can hide and the walls have been painted alot more realistically too... However... I do agree with the barrier thing... There was a rather inquisitive young Marmosetthat was trying to grab us... Thankfully... We had more sense that to offer our fingers as a chew toy!
Lol she grabbed me too whilst her mother peed on me! But I do think these are terrible exhibits, not because of the size but because of the openess and the mesh with no barrier. Whilst I had the sense to not let her pull my hand to the mesh, other people might not, and marmoset's teeth are sharp... I have no idea how this place passes zoo inspection, it's basically a copy of the original Dartmoor zoo only tidier.