whether the border is woven into the towel
Run your fingers over the line and look closely at the surface. A quality border should look like part of the towel fabric, not like a printed stripe or loose trim added afterward. A woven border is more meaningful because the pattern is formed during weaving rather than sitting only on the surface.
A hanging towel with a straight smooth woven border highlighted.
3
Look for straight, smooth border lines
Hold the towel by two corners and let it naturally. The border