 Meanwhile, The Hook was a key position on the left flank of the line held by the 1st Commonwealth Division and was the division's most threatened sector on the Jamestown Line.Held by the 29th British Infantry Brigade, the position consisted of a group of hills west of the Samichon River which dominated the Imjin River, to the south, and provided observation and fields of fire over a bend in the river as it turned towards Seoul.Loss of The Hook would force the UN troops to withdraw nearly to the next tenable defensive line on the high ground south of the Imjin River.