---
title: "Site architecture for SEO"
slug: "site-architecture"
category: "seo"
tags: ["seo", "site-architecture", "url-structure", "silo", "breadcrumbs", "information-architecture"]
status: "stable"
last_updated: 2026-05-15
summary: "URL hierarchy, silo structure, breadcrumb schema, depth-from-home, and slug conventions that let crawlers and readers reach every page in three clicks."
related: ["[[seo/internal-linking]]", "[[seo/content-clusters]]", "[[seo/technical]]", "[[seo/crawl-budget]]", "[[file-organization/index]]", "[[seo/structured-data]]", "[[seo/title-tags]]", "[[seo/glossary]]", "[[seo/audit-checklist]]"]
---
## Overview
Site architecture is the shape of the URL graph and the link graph laid on top of it. A flat, siloed architecture concentrates ranking signal on the pages that should rank; a deep, sprawling one dilutes signal across orphan leaves no crawler will spend budget on. Decide the shape before the first content page ships, because retrofits cost redirects.
## Keep priority pages within three clicks of home
The home page is the single highest-authority node on the site. Every click away from home halves the link equity reaching the next page, on average. A page buried five clicks deep ranks like the orphan it functionally is.
- Money pages, top-of-funnel guides, and category MOCs live at depth 1 or 2.
- Reference detail pages live at depth 2 or 3.
- Anything deeper than 3 is a candidate for promotion, merger, or removal.
Measure depth with a crawler that records the shortest path from the home URL. Screaming Frog, Sitebulb, and the open-source `wget --spider --recursive` all produce a depth column. See [[seo/crawl-budget]] for the budget side of the same problem.
## Map URL folders to topic clusters one-to-one
A category folder in the URL is a public commitment to a topic cluster. `/seo/` should contain SEO pages and nothing else; `/howto/` should contain step-by-step tutorials and nothing else. Mixing topics inside one folder confuses both the classifier and the reader.
```
/seo/technical
/seo/structured-data
/seo/internal-linking
/howto/audit-site-for-core-web-vitals
/howto/deploy-quartz-site
```
The folder is the silo. The MOC (`index.md` in each folder) is the silo entry point. See [[seo/content-clusters]] for the pillar-cluster pattern that fills the silo, and [[file-organization/index]] for the on-disk layout that mirrors the URL.
## Use short kebab-case noun-phrase slugs
A slug is a UX surface; users see it, share it, and type it. Keep it short, descriptive, and stable.
- Kebab-case. `meta-descriptions`, not `metaDescriptions` or `meta_descriptions`.
- Noun phrase, not a sentence. `audit-checklist`, not `how-to-audit-your-site`.
- No stop words unless they change meaning. `internal-linking`, not `the-internal-linking-guide`.
- No dates, no version numbers, no author initials. The slug is permanent; the body is mutable.
- Match the slug to the H1 intent. Drift between the two is the most common cause of a Google rewrite.
Once a slug is published, treat it as an API. Renaming a slug requires a 301 and breaks every external link until link rot resolves.
## Render breadcrumb schema on every page below root
Breadcrumbs serve two readers: the human who wants to navigate up, and the crawler that uses the BreadcrumbList JSON-LD to label the page's place in the hierarchy. Render both.
```html
```
```json
{
"@context": "https://schema.org",
"@type": "BreadcrumbList",
"itemListElement": [
{ "@type": "ListItem", "position": 1, "name": "Home", "item": "https://example.com/" },
{ "@type": "ListItem", "position": 2, "name": "SEO", "item": "https://example.com/seo/" },
{ "@type": "ListItem", "position": 3, "name": "Site architecture" }
]
}
```
The visible breadcrumb labels must match the JSON-LD `name` values exactly. See [[seo/structured-data]] for the full schema rules.
## Audit for orphan pages every quarter
An orphan page is any URL with zero internal inbound links. Crawlers find it only via the sitemap, and rankings reflect that. Run a site crawl, intersect the URL set with the link graph, and treat the difference as the orphan list.
- Link every orphan from at least one MOC and one peer page.
- If no peer page makes sense, the orphan is off-topic; remove or move it.
- Re-run the crawl after the fix and confirm zero orphans.
The same crawl produces the depth report; do both passes in one job.
## Avoid dead-end leaf pages
Every page should link out to at least two siblings and one parent. A page that only links to itself drops the reader and the crawler into a cul-de-sac. Use the `related` frontmatter field and inline wikilinks to enforce this; see [[seo/internal-linking]] for the link-anchor rules.
## Common errors
- Deep nesting that buries priority pages. `/category/subcategory/sub-subcategory/page` reads tidy on disk and ranks like an orphan. Flatten to two segments.
- Mismatch between URL slug and breadcrumb label. `/seo/site-architecture` rendering as "Site Architecture Best Practices" in the crumb confuses the classifier. Match exactly.
- Orphan MOCs. A folder index that no other page links to is itself an orphan. Link every MOC from the master index.
- Renaming slugs without 301s. Every external backlink to the old URL becomes a 404. Always redirect; see [[seo/title-tags]] for the related title-stability rule.
- One H1 per page violated by the breadcrumb. The crumb is a `