Site structure is one of the most important SEO concepts to understand if you're looking to improve your organic traffic. With an ineffective site structure, you will not give Google the signals it needs to understand how the content on your site is grouped and organised. You’ll also dilute the impact of any external links that you achieve due to PageRank not being effectively distributed to the places you want.

Alongside the SEO implications, a poor site structure is not great for UX (user experience) and can impact things like the amount of time someone spends on your site, bounce rates and more (more on this later in the article).

First, you need an understanding of PageRank

PageRank is an algorithm created by Larry Page and Sergei Brin in the early days of Google that creates a score for each page on the web-based that aims to measure the value of a page. It creates this score based upon the links it has received from other pages on the web.

By doing this, it creates a 'link graph' that indicates which pages are of higher importance based upon how high the score is.

The PageRank score assigned to the page is distributed evenly between the outbound links that it has. So in a simplified example, if a page has a PageRank of one and links to four other pages each page would receive 0.25 PageRank.

If you’ve never properly read up on the PageRank algorithm, I’d recommend this article by Ahrefs.

Keep high importance pages close to high authority pages

So that PageRank reaches the pages that you want to rank, you need to ensure they are close to other high authority pages. In most situations, the highest authority page on your site is going to be the home page. Therefore, it is key that you ensure pages on your site with a high potential to drive traffic and revenue are as close to the home page as possible.

In some situations when auditing site structure you will find that pages with URLs that have a high opportunity for traffic are 4+ clicks away from the home page. In the case of an ecommerce site, that could mean that important product pages struggle to rank because they are getting less PageRank. This is called a ‘deep’ site structure and an example of what that could look like is below:

deep site structure

In the above example structure, the site is heavily categorised but completely lacks deep-links to product pages and sub-categories from the home page. 

Unless the site has a lot of external links pointing to deeper within the site, the product pages are not going to rank anywhere near as well as what they could do.

When thinking of site structure, you want to keep it as flat as possible. For example, the home page should link to all your high importance category pages. You could also utilise the dropdown menus within the header of the site to provide deep links to further sub-categories. Here is an illustrative example of a flat site structure:

flat site structure

You can see in the above example more top-level categories are linked to which then link directly to products and further paginated pages within that category. By the time we are 3 clicks deep into this site structure, the amount of paginated pages and products for Google to crawl has grown exponentially. 

 Don’t just look at the home page

The concept of ensuring high authority pages link to other high importance pages does not just apply to the home page either. So whilst getting a flat site structure is a great start, there is still plenty more you could do here.

When you’re looking at your site structure you want to also pick out any other high authority pages to check where they are linking to. My default tool for looking at this is Ahrefs Site Explorer, just go to the ‘Best By Links’ report on your domain and look for high UR URLs. 

In the below example on a popular travel site, we’d want to have a look at the holidays or hotels page to see how well they distribute their PageRank to other pages.

ahrefs best by links travel site

Some further examples in practice

Once you have a flat structure you want to look at other ways in which you can bring pages closer to high authority pages. You can do this by adding deep-links from these pages to important pages that may be found deeper within your site architecture.

deep links

Keeping to the ecommerce theme, on the home page you could just simply introduce a grid that links out to the top sub-categories on a page.

category links example

Or, if you’re trying to bring product pages closer you could introduce a best sellers block with deep-links.

best seller wireframe

Another approach we often see in site’s with a large number of pages is implementing long lists of links found within something like an accordion or tabbed navigation.

accordion links example

This is pretty common when it comes to either job or travel sites just because of the sheer size of them. In most cases, users will utilise the search function usually found at the top of the page on sites like this, so these links are really more of a secondary way to navigate the site and it allows it to be easily crawled and indexed

Increasing the number of links to important pages by adding more columns/rows in the grid or by adding a carousel like in the best sellers example is a great way to make sure PageRank gets sent to all your important pages. One thing you do want to try and avoid is diluting PageRank too much with too many links on one page (more on this later).

Link vertically and horizontally

When navigating your site, make sure you're giving users the ability to move both vertically up and down your architecture as well as horizontally to related pages.

Add vertical links with breadcrumbs

One way in which you can ensure users can navigate vertically is by including breadcrumbs on your site. These are pretty common on most sites and they look a bit like the below:

Authors > John Grisham > The Reckoning

Breadcrumbs have the added benefit of letting users and Google know exactly where they are within your site architecture and gives a strong indication towards how you have decided to organise it.

Whilst adding breadcrumbs, make sure you also mark them up with relevant structured data to give a stronger signal to Google on how information is organised.

json ld structure data example

Examples of horizontal links

Horizontal links allow users to find information that is related to the page they are currently on. Examples of this could be:

  • An article that is related to the one they are reading
  • A product category that goes with products from a different category (e.g. mattresses and bedding)
  • Job listings that are related to the one you are looking at

Below is a simplified example of how that could look. There is one category linking to a related category alongside products within each category linking to each other:

horizontal linking example

Organise your site into logical hubs

Creating silos on your site is a great habit to get into so that the information architecture is clear for both users and Google. We tend to call this a hub and spoke approach, but either is fine. 

The idea is that your site should be made up of topical hubs that includes core information about a topic which then links off to secondary bits of information (spokes). 

Implementing a hub and spoke structure on your site makes it easy for Google to see you cover a topic well and that you’re an expert. Because of that, you’re more likely to be a good match for the user’s intent and rank better.

We’ve created an example top-level hub and spoke structure for an imaginary travel site:

hub spoke structure

In the above example, each destination would be a hub that would include on the page things such as:

  • Links to Sub-categories (counties and cities in the destination)
  • Overview content about the destination
  • Deep-links to hotels

It would then link out to further informational content on various long-tail queries people search around the destination. 

Focus on internal links within the main content of the page

Whilst this isn’t a confirmed algorithm, it is likely Google uses some kind of algorithm to increase the weighting of PageRank for links found within the main content of the page.

The basis of this speculative suggestions comes for a Google Patent which discusses a reasonable Reasonable Surfer model.

What is the Reasonable Surfer model?

The Reasonable Surfer Model refers to a patent that Google originally filed back in 2004 and then refiled with an update in 2012. The patent suggests that the PageRank passed from a link would increase or decrease depending on various features such as font size, colour, anchor text, position on the page and more.

reasonable surfer

If you want the full details, I’ll defer to Bill Slawski who has a great write-up on the patent here.

So what should I do about it?

Think about how you utilise the main content of your page for internal linking. Make sure you aren’t just relying on a mega menu in the header of your page to get links to important pages and instead weave internal links into the actual content of the page.

Don’t dilute your PageRank

It’s always important to remember when building out your site structure that you shouldn’t have too many links outlinks on any single page. This is especially the case if you want to use that page to funnel PageRank into other high priority pages.

This is because the PageRank passed from one page to another is split between the number of outgoing links the page has. If you've got a high authority page like your home page which then links out to 400 other pages, you'll be dividing the PageRank on the page by 400. In the simplified example below, a page has a PageRank of 1 and links out to four pages, resulting in each page holiday 0.25 PR.

page rank dilution 1

When more links are added, the PageRank is diluted further.

page rank dilution 2

This all depends on how much authority you have on your site. But if you haven't got much and you're dividing it between a large number of pages you may find it harder to rank than you would if it was a smaller site.

You may find it much better when you start out to pick a focused niche and then as you grow and gain links, start making your site larger and adding more links from high authority pages.

The below quote from Matt Cutts summarises this quite nicely:

At any rate, you’re dividing the PageRank of that page between hundreds of links, so each link is only going to pass along a minuscule amount of PageRank anyway. Users often dislike link-heavy pages too, so before you go overboard putting a ton of links on a page, ask yourself what the purpose of the page is and whether it works well for the user experience.

Matt Cutts, March 9 2009

Use your URLs to indicate the structure

Another great way of indicating the structure of your site is organising your site into directories and sub-directories.

I've created an example URL structure below for a travel site so you can see how thinking ahead and organising your pages in a logical manner can give a really strong indication of site structure.

heading structure example

Site structure is as much about UX

To me, site structure is an SEO concept where you should be thinking of UX (user experience) as much as you should be trying to improve your organic traffic. This is because changing anything to do with site structure will have a significant impact on both.

As you delve more into SEO you'll find this is the case with many SEO concepts. In a lot of cases, making a UX change impact SEO and vice versa. Site structure is an obvious one where it impacts both.

seo ux overlap

For example, via internal linking and site structure auditing, you may find that one of your high selling products is not being internally linked to very well. At the moment, it’s 4 clicks away from the home page and has a minimal number of internal links.

So, you decide to do a few things. First, you get this product listed on a new bestseller block on your home page. Next, you tweak your related products algorithm that shows on your product pages so that it is more heavily weighted towards showing best selling products. You also decide to implement a banner on category pages above the product grid that lists this product above-the-fold. 

This is all great for UX, more users are finding this product and because of this, you’re selling more of it.

But consider the SEO implications of what you have just done:

  • The product is now on the home page - It’s now on the highest authority page of your site, so it’s getting more PageRank
  • It is linked to more from related products - It now has a large increase in the number of internal links, so again more PageRank is passed
  • It’s primary category links to it above-the-fold - Google passes more PageRank to URLs that are more likely to be clicked

Hopefully, you’re now seeing my point. When working on site structure, you should really be thinking about UX as much as you are about SEO. The difference between a good SEO and a great one is when you understand this and begin focusing more holistically on how to improve your site.

Final words

Hopefully this article has given you some insights into the things you should be looking for when created your site architecture. I'll be writing more on the topic soon so keep an eye out for more!