Joseph Laux (1904-1991) used rocks from Skyline drive and elsewhere, glass from Southern NJ blast furnaces, shells, statuettes and crockery embedded in what appears to be a portland cement blend to build his castles, walls, bridges and towers.
The site is in a yard on Route 41 in Deptford, NJ- an occasional route to work for me. There's rumored to be 2 more elsewhere in the area. I went for a 1024px "filmstrip" for the immersion effect. Not sure if I like it - but you definitely get detail.....