Spiral staircase

There's nowhere better to hide on a cold damp day than in the hothouses at the botanic gardens. The sudden rise in temperature caused my camera lens to fog over, hence the weird steamy appearance of this picture.

You have to look pretty hard to see it (it looks better large), but amid all that lush foliage is a beautiful wrought-iron spiral staircase. I used to come here on my own when I was a kid and wander about among the palms and ferns, breathing in the hot, humid, scented air, and dream about one day living in a place with plants like these. But it was the strictly out-of-bounds spiral staircase I longed for most - what was up there? where did it lead to? I still can't see far enough up through the leaves to know. I still really want to climb it...