LH Post Type Archive Nav Menu Items lets you link to the archive of any post type that has one, including custom post types, from your site’s navigation. WordPress lets you link to individual posts, pages and categories, but has no built-in way to link to a post type’s archive, such as a list of all events or all products.
The link’s address is worked out from WordPress when the page is shown rather than typed in, so it keeps working if a post type’s archive address changes, and it is marked as the current item when a visitor is on that archive.