Why do you think the cross of lothair was created ?

The cross was originally created for one of the Ottonian family, the heirs of the Carolingian family, about a century after Lothair's death; perhaps for Otto III, the Holy Roman Emperor. It seems that as soon as it was made, it was donated to the Cathedral. The Cross is still used nowadays in processions.

Explanation:

your word would be isle.

isle is an island or peninsula especially a small one.

if you add the letter "a" you get aisle, which is a passage between 2 rows of something like chairs, shelves, or something else.