Wikipedia:Page name/sub/page/name1/sub/page/name2/subpage level 3

Notice, in the upper left of the page, the breadcrumb navigation links leading to the root page.

{{Subpage help}}
Equalities? Variables and markup Live rendering
On subpages, these three: fullpagename Wikipedia:Page name/sub/page/name1/sub/page/name2/subpage level 3
namespace:basepagename/subpagename Wikipedia:Page name/sub/page/name1/sub/page/name2/subpage level 3
../subpagename Wikipedia:Page name/sub/page/name1/sub/page/name2/subpage level 3
On subpages, these two: pagename Page name/sub/page/name1/sub/page/name2/subpage level 3
basepagename/subpagename Page name/sub/page/name1/sub/page/name2/subpage level 3
On root and 1st sub/page: basepagename Page name/sub/page/name1/sub/page/name2
rootpagename Page name
On subpages, these equal nav links. [[../]] Wikipedia:Page name/sub/page/name1/sub/page/name2
[[../../]] Wikipedia:Page name/sub/page/name1/sub/page
[[../../../]] Wikipedia:Page name/sub/page/name1/sub
List subpages of this page

[[../../]] and [[../../../]] are redlinks because of the two slash / characters. But on [[../]], you will find [[../]] and [[../../]] are redlinks.