# Changing image texture as height increases and using colorRamp with image texture

I am trying to make a landscape scene. I want the landscape to have 4 different images as textures. The images should change as the height increases. I was able to do this with 2 images but when I increase the images it goes wrong. Also I found examples on stack which were using color ramp. Also when I use a mapping node for my images, the result is having only one Image. I use cycles engine.

I want something like this but instead of colors i want to use images

Use different ramps, each one with a different increasing range, to map the information from the $Z$ axis.