Why you need a 2 wheel cart in Europe?
Barcelona, Spain - No cars is the reason.

This little 2 wheel cart for groceries and everything is everywhere.

Made by Rosler in Spain. http://www.rosler.com
Send money Rosler.

This is the Correos or Postman.
What is interesting about these bags is that with the absence of cars. You must figure or have a ways to carry things. Men, women, boys, and everyone had one of these

I am trying to figure out how to put wheels on my backpack that would work.