Walk on __, Tread Very Carefully
This page is the CodyCross answer for the clue below from Architectural Styles, Group 1163, Puzzle 5 (Flying Buttress).
Question is: Walk on __, Tread Very Carefully
and the answer is: EGGSHELLS
Word Meaning:
EGGSHELLS — plural of eggshell
Definitions from Wiktionary.