Board Thread:Bug Reports/@comment-210.55.186.182-20160824004053/@comment-27516710-20160824050838

You can use Dinnerbone's online calculator to get the region file, or, simply divide the X,Z by 512 and round down to get the region file number (if the coordinate is negative then you round up)

Ex: x=3448/512=6.73  z=6344/512=12.39

Rounded down becomes 6,12

(If they are negative then it would be rounded to -7,-13)

So the region file to delete for these coordinates would be (r.6.12.mca) - for the LOTR mod these are located in /Middle Earth/region/