Reddit reviews Secret London - An Unusual Guide ('Secret' guides)
We found 1 Reddit comments about Secret London - An Unusual Guide ('Secret' guides). Here are the top ones, ranked by their Reddit score.
Jonglez Publishing
I'd suggest buying a book such as this one and flicking through for inspiration:
https://www.amazon.co.uk/Secret-London-Unusual-Jonglez-Guides/dp/236195110X/