The two countries also agreed to use the watershed principle to determine the remaining undelimited portions of the border.

Only a portion of the border is delimited through agreements.

Some 31,400 people crossed just that portion of the border in the first nine months of 2010.

The river forms a portion of the international border between the two countries.

It forms a portion of the international border between China and Vietnam.

It forms a portion of the border of the axilla.

It forms a portion of the international border between Brazil and Bolivia.

For its entire course, it forms a short portion of the international border between Argentina and Brazil.

Small demarcated portions of the border are fenced on both sides.

It lies along a portion of the national border with Ethiopia.