Colonia Marciana Ulpia Traiana Thamugadi, or Thamugadi, was a military colony founded by the Roman Emperor Trajan in 100 AD.
From Schoder's lecture notes:
THAMUGADI (Timgad): founded 100 by Trajan, built by soldiers of III Legion. Destroyed early 6 c. by natives but rebuilt by Byzantines; wrecked by Arabs late 7 c.
Air view: 1: Th., forum; Decumanus top-bottom, Arch Trajan at top, Capitolium at l. above Th; Baths rt.
X Up Cardo Maximus twd Forum
Decamanus at Cardo crossing, twd. Arch Trajan
Library: front court, semicircular reading-rm byd.
X East Market, stalls
Triumphal Arch at W exit, c. 210; statues.