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If you have Juicebox-Pro, you could use the Back Button to include a link to any web page you like (via the backButtonUrl configuration option).
You can see the Back Button in action in the top-left corner of this demo gallery.
For reference, a list of all Back Button configuration options can be found here.

Please note that the Back Button is a Pro feature which is not supported by Juicebox-Lite (the free version).
However, you can include links in a Juicebox-Lite gallery by using HTML formatting within either the Gallery Title or image titles/captions as noted in the following FAQs.
How do I add HTML formatting to image captions and titles?
How do I add HTML formatting to the Gallery Title or Back Button?

For example, a link in an image caption might look something like this:

<caption><![CDATA[<a href="http://www.example.com/index.html">Click here.</a>]]></caption>

In JuiceboxBuilder-Lite, you would just need to enter:

<a href="http://www.example.com/index.html">Click here.</a>

... JuiceboxBuilder-Lite will add the <caption> and CDATA tags when the caption is written to the gallery's 'config.xml' file.

Alternatively, instead of having a list of galleries on a separate page, you might like to have the list always visible and have your links display the chosen gallery (alongside the list).
Take a look at 'Switching between Multiple Galleries using JavaScript' in the Embedding Multiple Galleries support section.
You'll see there are links (which are always visible) to 2 different galleries and the gallery being displayed on the page can be selected (and changed) by clicking the links.
You can view the source of the web page in your browser and copy/modify the code to suit your own needs.
(You might also like to take a look at 'Using a Resizable Gallery with a Header'. The examples here use separate pages for each gallery but the navigation menu is duplicated on each page alongside the galleries.)
The multiple gallery examples all work equally well for both Juicebox-Lite and Juicebox-Pro.

I hope this helps and points you in the right direction.