Size of a base?

[autodctr]

I am building an HO sized layout and am trying to find out / figure out how big this would be in real life. I have seen posts before, but cannot find them. What is the size of one base?

 

[G.M.]

a Trainz baseboard is 720m normally in 1:1
if you work in h0 1:87 it would be 720:87=8.27582m

 

[C_Blabsky]

So a little over 27 feet, for us Americans.