Which area of nursing requires knowledge of anatomy

For nurses who have worked in various areas, which area of nursing would you say requires an RN to have a the greatest amount of anatomy knowledge? ICU? OR?

thanks.
Each area of nursing requires different aspects of anatomy. The Physiologic part is very important in ICU. OR nurses who scrub would benefit from good knowledge of location of organs, etc. OB would need to know reproductive systems. As a cath lab nurse, I need to understand cardiac and vascular anatomy.