I grew up in fairly extreme poverty. There wasn't even a park near out home that was safe when I was young. Part of this bridge was near my house, as in it was our backyard basically. Those X shaped struts are actually shaped like a slide, lips on the side of the metal to grab hold and shimmy up.
That was our neighborhood slide for me and a couple other kids. Use to drive my mom nuts when she would come out on the back porch and see me.