Grid nineteen by thirty-seven is a planetary grid location on the UEG colony Sigma Octanus IV, it is a location in the jungle wilderness of the planet, just on the outskirts of the city of Côte d'Azur. It is covered by dense foliage but has enough of a clearing to support a significant encampment.[1]

Battle of Sigma Octanus IVEdit

Main article: Battle of Sigma Octanus IV

In 2552, during the Battle of Sigma Octanus IV, Grid 19 x 37 was the site of a Firebase, Alpha Headquarters. This base was attacked and almost completely destroyed by Covenant forces and the subsequent glassing.[2]


  1. Halo: The Fall of Reach, page 205
  2. Halo: The Fall of Reach, page 199