You can place an "anchor" either on a resource within the Workbench, or at a specific line within a file, by creating a bookmark. Then you can use the Bookmarks view to return to those files quickly.

The Bookmarks  view (Window > Show View > Bookmarks) displays all bookmarks that you have created. 

Related concepts
Tasks view

Related tasks
Creating a bookmark for an entire file
Creating a bookmark within a file

Deleting a bookmark
Adding line items in the Tasks view
Associating a task with an editable resource

Related concepts
Tasks view
Problems view

Related reference
Bookmarks view