Breadcrumbs help users (obvious back-nav) and Google (which shows them in rich results). Add them to every page below the top level, mark them up with BreadcrumbList structured data, and match the order in the URL.
Breadcrumbs help users (obvious back-nav) and Google (which shows them in rich results). Add them to every page below the top level, mark them up with BreadcrumbList structured data, and match the order in the URL.