A cardboard container of substantially rigid construction comprises a peripheral wall panel defining a hollow body, the wall panel including an in-turned flange formed along a peripheral edge thereof, the flange extending continuously along an entire length of the peripheral edge of the wall panel and being foldably and integrally connected to the wall panel by a continuous score line, the flange further having opposite ends held in abutment with one another within the hollow body such that the flange is held in a state of compression and retained within the hollow body in face-to-face engagement with the wall panel without otherwise being secured to the wall panel; and a transverse member being retained within the hollow body by the flange.