Posted by MattBlissett on Apr 25, 2019; 9:28pm
URL: https://discuss.asciidoctor.org/How-can-I-make-asciidoctor-links-dynamic-to-the-file-system-tp6860p6874.html

You can go "up" in a directory with the path "../".

Within Y.adoc, you would use the relative URL ../X.adoc.