Whether in the snow, rain, cold or heat, the Caisson Platoon is out in Arlington National Cemetery for funerals every day, Mondays through Fridays. Using a caisson is steeped in tradition and history, going back to the day when field artillerymen used the caissons to transport 75mm cannon ammunition. The caissons, which were built in 1918, now carry the remains of those who served the nation with honor and distinction. A caisson team consists of seven horses and four riders. Three of the horses hitched to the caisson are unmounted, because the field artillerymen of the day used the off-side horses to carry additional gear, Ford said. Here, the white caisson team turns into the cemetery from the Old Post Chapel.