A couple make their way through wrought iron gates leaving the British Museum's south entrance while behind them crowds are milling about in the museum's forecourt.
We need to inspire and enable everybody to care for the historic environment © Historic England. AA077685. Photographed by John Gay in 1962-65
We need to inspire and enable everybody to care for the historic environment © Historic England. AA077685. Photographed by John Gay in 1962-65

Publishing Accessible Web Content

We need to inspire and enable everybody to care for the historic environment. To do this, everything we publish has got to meet accessibility standards – and laws.

Accessibility is affected by what you write, how you design it and the file format you choose to publish it with.

Creating accessible web pages doesn't just benefit people who have access requirements. Accessible content is easier for everybody to find and to understand, which makes it easier and more likely for people to act on what you're saying.

Writing text

The code and templates behind the website, looked after by the Digital team, have a good level of accessibility so there isn't much extra that you need to do.

Find out how to write for the web


Some people can't see your images, or can't see them as clearly.

Write alternative text to describe your image.

Avoid putting text in images, but if you do have a more complex infographic then write a text alternative.

The Historic England website can display a short text alternative near the image, or link through to a standalone page if the image is more complex.

More about preparing image content


Videos need either subtitles (closed captions), audio description or a text alternative depending on the way they communicate information.

A closed caption is a text file that contains a transcript of the words spoken.

Open captions are 'always on' captions that are part of the video itself. Open captions do not assist with accessibility as they are graphics not text.

Requirements for videos:

  • Videos with narration: Closed captions
  • Videos with no narration: Text alternative or audio description.
  • Videos with narration and visual information: You may need closed captions as well as a text alternative or audio description.


Audio files, like podcasts, should have a transcript available as a text alternative.


PDFs are commonly used on the web but they are becoming – if not already – a legacy format. They have production and accessibility issues.

  • They're a print format. Ask yourself if you really expect your reader to print the document themselves and read from paper.
  • They're not very accessible. Without significant intervention PDFs are not an accessible format, so they fail our requirement to publish in a non-discriminatory way.  
  • They're harder to correct and update. Because of the design and production process, any updates to PDFs are very time consuming and they are likely to go out of date with broken links and incorrect branding.

HTML (the format used for a web pages) is typically much more accessible and easier to update. HTML is our preferred publishing format. New page templates will become available soon (late 2020) that will let us create more complex and interesting page layouts for the types of information that we would usually have published as PDF.  

Expectations for PDFs we publish

PDF files need to be tagged with the heading structure and reading order so that any user can navigate and get information from them.

PDFs created, published or funded by Historic England must be tagged.


  • Headings structure is described.
  • Images have alternative text descriptions.
  • Table of contents bookmarks are created for documents longer than 10 pages.
  • Reading order is set so the elements are read out in the correct order.
  • Language of the text is set.


  • Tag tree is in correct reading order – the tag tree does not always reflect the reading order set above so it has to be checked separately.
  • Run the full Acrobat accessibility checker – any errors should be fixed where possible.

Acrobat's features improve with each version so older PDFs might not meet the advanced criteria above. Any PDF being published after September 2020 should.

Find out how to make a document accessible

Websites & apps

If you're publishing content to HistoricEngland.org.uk you don't need to worry about the accessibility of your templates. If you have a project that is creating or commissioning a standalone website or app there are further technical considerations that are vital to accessibility. You will need to talk to Digital Team, email them [email protected]