stair posts on rock?

[nicklang907]

Hi,

How does one go about building stairs on a steep area that has mostly
a thin layer of soil with rock underneath? I am just guessing, but I
think I need to drill through the soil and into the rock and then set
posts in concrete and then connect the stairs to these posts. Does
this sound realistic? Any advice would be helpful (this is in the
area of the Canadian Shield).

Thanks!