Routes are specified in the `site/routes` configuration section of your website. This should be a list, where each item is a mapping with the following entries:

url: The URL pattern for the route.
source: The name of the source this route is for.
func (optional): The name of a templating function you can use to generate URLs for this route.

The URL pattern typically includes placeholders for information obtained by the source, like a blog post's date and slug. For example:

site:
  routes:
    - url: /myblog/%year%/%month%/%slug%
      source: posts

To know which placeholders are available, see `chef help routes_params`.