It's a neat subject. It was built to house The Great Exhibition of 1851.
The wiki page on it talks about the toilets.
The first modern pay toilets were installed, with 827,280 visitors paying the 1 penny fee to use them. The toilets remained even after the exhibition was dismantled. "Spending a penny" became a euphemism for using a toilet.
It's a neat subject. It was built to house [The Great Exhibition of 1851.](https://www.thoughtco.com/britains-great-exhibition-of-1851-1773797)
The [wiki page](https://en.wikipedia.org/wiki/The_Great_Exhibition) on it talks about the toilets.
>The first modern pay toilets were installed, with 827,280 visitors paying the 1 penny fee to use them. The toilets remained even after the exhibition was dismantled. "Spending a penny" became a euphemism for using a toilet.
Bill Bryson's book 'At Home' has a very interesting section about the Crystal Palace. It was a ground breaking building and the first large public space to have flushing toilets, the toilets we more popular than many of the exhibits.