Include results in "Object of class Craft\ElementCriteriaModel could not be converted to string" I have a template with just this code:

{% include 'amenities/_types/amenities' %}


This results in a template error: 

Object of class Craft\ElementCriteriaModel could not be converted to string

Never encountered this one before. What is causing this?
Well I now see this error was caused by the included template and not the fact that I was trying to include a template. 

I thought that the error message would show the error on the included template that was the actual source of the problem, but it was just referencing the include as the error.