thanks, that information was useful.

I had a HO scale train set that I played with while growing up (actually my fathers), and remember the fun I had with it.  Now, two plus decades later, I am getting back into it to introduce my son to the hobby.  I have always been a multi hobby person and have always wanted to put up a train layout.  Now that he is old enough not to just grab and tear things up, I am doing the layout.  I have a couple of books introducing me to the EZ track system, wow, the technology has come along way in 20 plus years.  My question is about scale size.  how do I figure the size of road size, sidewalk width and height in corolation to the size of the buildings and other comercially available diaroma?