El coliseo cuenta con ocho escotillas y todas ellas fueron utilizadas como celdas colectivas. Cada una albergó aproximadamente entre 300 y 400 detenidos. Las escotillas y los camarines fueron los lugares de reclusión para los hombres detenidos.

En los muros aún se distinguen los grabados hechos por los prisioneros con llaves u otros elementos. Grabaron pequeños mensajes, sus iniciales, estrofas de canciones, una fecha.

Aunque comenzaba la primavera, la humedad, el cemento y los helados muros hicieron aún más inhóspitos estos lugares. Las noches eran heladas y los prisioneros debían dormir en el suelo y también en baños e improvisados camarotes, que eran compartidos en turnos. Después de algunos días se repartió una frazada por persona. Algunos sectores se inundaban de agua después de una lluvia, y aún en esas condiciones debieron mantenerse en el lugar. Las enfermedades afloraron, agravadas por la violencia física a la que eran sometidos los prisioneros a toda hora y la falta de alimentación e higiene adecuadas.

El hambre fue agudo y permanente. La alimentación era preparada y traída desde el Estadio Militar en el Parque O’Higgins. Consistía en un desayuno muy temprano, de un tazón de café de higo con un pan, y luego una comida al día, generalmente legumbres, sopa o fideos. En más de una ocasión, llegó la comida en mal estado. Al comienzo la comida no alcanzaba para todos, por lo que los mismos detenidos se organizaron en escuadrillas para distribuirla a los distintos lugares de reclusión. Cada detenido tenía un plato y tazón que debía cuidar.

A partir del 22 de septiembre comenzaron a sacar a los detenidos a las graderías. Esto se constituyó en una rutina de las primeras horas de la mañana y posteriormente de algunas tardes, que les permitió hacer ejercicios y compartir entre ellos, pero también en un “lugar de espera” donde eran llamados a interrogatorios y torturas.

Thousands of people, men, women, and children, both Chileans and foreigners, were detained in the stadium, incommunicado and without any formal charges. Not all of them were left-wing militants or even involved in anything. Many people were also arrested on suspicion, or because someone reported them for any reason, simply for being foreigners, for violating curfew, for appearing left-wing, or were caught up in the large general raids on factories and communities. They were workers, farmers, technicians, professionals, and public officials. There were artists, students, housewives, tourists, and even diplomats detained. In the raids, the police and military forces also took the opportunity to arrest well-known common criminals who ended up living with political prisoners and received equal or worse treatment.

On September 11, 2003, the National Stadium was declared a Historical Monument in its entirety.

The coliseum has eight hatches, and all of them were used as collective cells. Each one housed approximately between 300 and 400 detainees. The hatches and dressing rooms were the places of confinement for the male detainees.

On the walls, we can still see the engravings made by the prisoners with keys or other elements. They engraved small messages, their initials, song verses, a date. Although spring was beginning, the humidity, cement, and icy walls made these places even more inhospitable. The nights were freezing, and the prisoners had to sleep on the floor and also in bathrooms and makeshift bunks, which were shared in shifts. After a few days, one blanket was distributed per person. Some areas were flooded with water after a rain, and even under those conditions, they had to remain in place. Diseases emerged, aggravated by the physical violence to which the prisoners were subjected around the clock and the lack of adequate food and hygiene.

The hunger was acute and permanent. The food was prepared and brought from the Military Stadium in O’Higgins Park. It consisted of a very early breakfast of a fig coffee cup with a bread and then one meal a day, usually vegetables, soup or noodles. On more than one occasion, the food arrived in poor condition. At the beginning, the food was not enough for everyone, so the detainees themselves organized into squads to distribute it to the different places of confinement. Each detainee had a plate and bowl to take care of.

Starting on September 22, the detainees began to be taken to the stands. This became a routine of the early morning and later some afternoons, which allowed them to exercise and share among themselves, but also in a “waiting area” where they were called for interrogations and torture.