@NonNull
    public Uri getBaseUri() {
        return persistableFolder != null ? persistableFolder.getFolder().getBaseUri() : this.uri;
    }
returns this folder's current BaseUri (below all subfolders). This value is volatile if this folder's type is volatile (e.g. {@link FolderType#PERSISTABLE_FOLDER})
main/src/main/java/cgeo/geocaching/storage/Folder.java