I remember being taken here when I was small and f...

I remember being taken here when I was small and finding it to be fascinating. I recently took my own son there and he was still as impressed by it as I remember being. The main attraction is the obscura on the top of the building but as you work your way up you are shown a host of different optical illusions, some really meas with your perspective, with each being illusion being explained.
Well worth a visit if you are a visitor or a resident and especially good fun for families.