ByLastmod

Returns the given page collection sorted by last modification date in ascending order.

When sorting by last modification date, the value is determined by your site configuration, defaulting to the lastmod field in front matter.

{{ range .Pages.ByLastmod }}
  <h2><a href="{{ .RelPermalink }}">{{ .LinkTitle }}</a></h2>
{{ end }}

To sort in descending order:

{{ range .Pages.ByLastmod.Reverse }}
  <h2><a href="{{ .RelPermalink }}">{{ .LinkTitle }}</a></h2>
{{ end }}