Wow, that looks pretty cool! Huge cage, I love the space! I'm sure you just took the picture without hay or hidey houses so it would be clean and we could see the piggies. Thanks for sharing! =)
Can I just add, guinea pigs don't need hidy house things - it just makes them more scared of people! I've had 19 guinea pigs in my life and all of them are soo friendly without the hidy houses (I have tried them, but the guinea pigs I tried them on became very scared) It just means they will run into it everytime you pick them up and they'll learn that and never like being picked up. But I would advise you to have something over the top of the cage and one end, as it isn't fair to have nothing at all. - and they need hay to eat and sleep in.
I agree, more hay, and toy. lots of room to run though
90katrinna90 Guinea pigs DO need hidy houses, if you dont want to buy them you can just give them a couple upside down boxes with doors cut in so they can play and investigate. It wont make them more scared. If they run in there when you go to pick them up it means they were scared of you anyway and now they just have a place to go, I'd like to have a place to go to hide if I were living with giants.