wget

see also: cURL

wget -r -np -k -p --adjust-extension $URL

Recursive Retrieval Options
    -r
    --recursive
        Turn on recursive retrieving. The default maximum depth is 5.

-np
--no-parent
    Do not ever ascend to the parent directory when retrieving recursively.  This is a useful option,
    since it guarantees that only the files below a certain hierarchy will be downloaded.

-k
--convert-links
    After the download is complete, convert the links in the document to make them suitable for local
    viewing.  This affects not only the visible hyperlinks, but any part of the document that links to
    external content, such as embedded images, links to style sheets, hyperlinks to non-HTML content,
    etc.

-p
--page-requisites
    This option causes Wget to download all the files that are necessary to properly display a given HTML
    page.  This includes such things as inlined images, sounds, and referenced stylesheets.

-E
--adjust-extension
    If a file of type application/xhtml+xml or text/html is downloaded and the URL does not end with the
    regexp \.[Hh][Tt][Mm][Ll]?, this option will cause the suffix .html to be appended to the local
    filename.