Valo I was the first planet in the Valo system. This system was located near the Cardassian border in neutral space. This planet had at least three moons. This was a Class M world. In 2368, Bajoran resistance leader Orta maintained his hidden base on the third moon of Valo I. Based on a tip from Keeve Falor, the USS Enterprise-D traveled to Valo I and made contact with Orta, who informed them that the Bajorans were not responsible for the attack on Solarion IV. (TNG: "Ensign Ro")
According to the script, the pronunciation for Valo was "VAH-lo". [1]
For the third moon of Valo, see unnamed moons.
According to the Star Trek: Star Charts, on page 47, the Valo system was located in the Alpha Quadrant.