The first, outpost, line ran from the village of Cau Giay near Paper Bridge, the scene of Rivière's defeat and death on 19 May, to the Pagoda of the Four Columns (Quatre Colonnes) on the Red River.
Garis pertama, pos terdepan, berlari dari desa Cau Giay dekat Jembatan Merah, tempat kekalahan dan kematian Riviere pada tanggal 19 Mei, ke Pagoda Empat Kolom (Quatre Colonnes) di Sungai Merah.