Rapid content audits, can this be done?

Content audits although immensely dull are essential to understanding an existing websites content. Content audits for larger sites where you're capturing each page and analysing the content page by page is obviously very time consuming. I'm wondering if there is a "lean" approach to auditing/quick way to understand a websites content without having to go through the entirety of the site?

An example I thought of was creating a sitemap of the site. This will give you an indication of the shape and size of the site. In terms of capturing content you would only be capturing the pages you believe are unique content types. Rather than going through the whole site. I guess though in order to discover the content types you would still potentially have to click through the whole site but it would save time of not having to capture all the URL's and describe each page.