Research

I looked into other souvenirs/products along a similar line to mine:

Products by Kidsonroof:

This company makes wonderful productss/toys out of recycled card board (amongst few other things) in a similar 'pop-out' way to my design idea.

Kidsonroof wishes to re-connect modern life with nature, rediscovering basic values. Kidsonroof offers an ecological approach to the act of playing. Stimulating creativity and imagination lies at the heart of Kidsonroofs products.

http://kidsonroof.com/new/

Pop-out cardboard city

Other products:

Pop-out cardboard boats/animals that you piece together as a 3D Jigsaw.

www.Ponoko.com 

This website not only has an interesting blog, but has the ability for you to design and make 2D and 3D  laser cut cardboard designs.  

It has not happened in the design for this project - but looking back I think it would be nice to make my product as eco-friendly as possible - Using recycled materials where possible.  Birmingham is a city which is always trying to encourage citizens and businesses to be as eco-friendly as possible and I think this product would have worked well (and retailed well) if made eco-friendly.