Short answers, pulled from the story.
Numantia is situated on the hill known as Cerro de la Muela above the modern municipality of Garray in Soria, Spain. Pliny the Elder classified it as a city belonging to the Pellendones tribe while other authors like Strabo and Ptolemy placed it among the Arevaci people.
The final siege began in 134 BC under the command of Scipio Aemilianus. An army of thirty thousand soldiers surrounded the city with a nine kilometer barrier that included towers, moats, and impaling rods designed to prevent escape.
Eduardo Saavedra identified the correct location in Garray, Soria in 1860 after some theories incorrectly placed it in Zamora until that year. Adolf Schulten began excavations in 1905 and located the Roman camps around the city.
Most inhabitants chose suicide rather than become slaves to Rome when famine spread quickly through the starving city after eight months of blockade. A few hundred survivors burned the city before surrendering after thirteen months total while the population numbered between four thousand and eight thousand souls at that time.
Miguel de Cervantes wrote a play called El cerco de Numancia about the siege while Antonio Machado referenced the city in his poetry book Campos de Castilla. Carlos Fuentes published a short story titled The Two Numantias in his collection The Orange Tree.