A sitemap is a structured representation of all the pages of a website and the links that connect them. It serves as both a map for visitors and a technical guide for search engine bots. When well-designed, it determines how easily a user can find information and how quickly Google indexes the content.
Click Depth and Crawl Budget: How Structure Affects SEO
The depth of a page refers to the number of clicks needed from the homepage to reach it. The deeper a page is buried, the fewer organic visits it receives, and the less frequently indexing bots crawl it.
A sitemap structured with a shallow hierarchy (a maximum of three levels) allows search engines to crawl all content without wasting their crawl budget. Deep pages, four clicks or more from the root, risk being ignored during automated crawling.
The concrete issue: if an e-commerce site categorizes its product listings under five levels of categories and subcategories, some listings simply won’t be indexed. Moving these pages up by two or three levels, by simplifying the categories, is often enough to make them appear in search results.
Consulting the sitemap of By Caroline and CO provides a concrete overview of a readable hierarchy where each page remains accessible with just a few clicks.
Web Accessibility and Sitemap: WCAG 2.2 Requirements
The WCAG 2.2 standard, which became an official W3C recommendation on October 5, 2023, and was revised on December 12, 2024, introduces criteria that directly impact the design of a sitemap.
A sitemap is no longer judged solely on its SEO logic. It must also ensure that navigation remains usable for people with disabilities, screen reader users, and those who navigate exclusively via keyboard.
Concrete Criteria to Follow in the Hierarchy
- Provide multiple ways to access the same page: main menu, search bar, HTML sitemap, and breadcrumb. A single access path is no longer sufficient.
- Maintain consistent navigation: menus and navigation blocks must keep the same relative order across all pages of the site to avoid disorienting the user.
- Ensure that keyboard focus is not obscured by a sticky header or a persistent banner. The “Focus not obscured” criterion of WCAG 2.2 specifically targets this issue.
These requirements change the way a sitemap is constructed: each page must be reachable by at least two distinct paths, and the navigation structure must remain consistent from one section to another.
Category Navigation: Organizing Content Without Multiplying Levels
The classic temptation is to create a category for each theme, then subcategories, and then sub-subcategories. The result: a sprawling hierarchy where the user gets lost and where search engines struggle to establish a clear hierarchy between pages.
A more effective approach is to group content into broad categories, then use filters or tags to refine the search. The structure remains flat (two to three levels), while granularity comes from the filtering system.
Breadcrumbs and Internal Links
The breadcrumb serves a dual function. For the visitor, it indicates their position in the hierarchy and allows them to navigate back to the parent category with one click. For search engines, it clarifies the hierarchical relationship between pages.
Contextual internal links complement this structure. A link placed in the body of an article to a complementary page strengthens the internal linking without adding a level to the hierarchy. This type of link also distributes SEO authority among pages, benefiting less visited content.
XML Sitemap and HTML Sitemap: Two Tools, Two Distinct Roles
The XML sitemap is a technical file intended for search engine bots. It lists the site’s URLs along with their metadata (last modified date, update frequency, relative priority). This file is not designed to be read by humans.
The HTML sitemap, on the other hand, is a page visible to visitors. It presents an organized list of the site’s pages, often in the form of links grouped by categories. Its utility is twofold: to provide direct access to any page on the site and to offer an alternative navigation path, in accordance with WCAG 2.2 recommendations.
Confusing the two is a common mistake. A site needs both: XML for indexing, HTML for user experience and accessibility. The XML sitemap is submitted via the Search Console; the HTML sitemap is placed in the footer or in the secondary menu.
What the XML Sitemap Does Not Fix
Submitting an XML sitemap does not compensate for poor structure. If a page is accessible only via the XML sitemap but is unfindable through standard navigation, search engines will assign it little value. The XML file signals URLs to explore, but the actual structure of the site remains the primary signal for ranking.
A well-constructed sitemap makes the XML sitemap almost redundant for small sites: if all pages are reachable within three clicks and connected by coherent internal links, indexing bots will naturally discover them. XML remains relevant for large sites, where the number of pages exceeds the spontaneous crawling capacity of bots.
The structure of a site is not an aesthetic choice. It conditions indexing, accessibility, and visitors’ ability to find what they are looking for. A sitemap that adheres to limited depth, offers multiple access paths, and clearly distinguishes the roles of XML and HTML covers the essentials of what search engines and users expect.
