Four iron(II) ions help assemble a container molecule (1), by bringing together two hemispherical resorc[4]arenes. The resorc[4]arene ligands are appended with four iminodiacetate moieties which act as ligands for the iron atoms. X-ray crystallographic analysis of 1 shows that the iron atoms are coordinated in an N,N-cis-fac manner and exhibit a trigonal prismatic geometry. When 1 is formed in water, six water molecules, hydrogen bonded together, occupy its cavity. However when 1 is formed with bromobenzene present in the water solution, bromobenzene is crapped in the cavity. Multinuclear NMR experiments (H-1, H-2, and F-19) demonstrate the pH-dependent encapsulation of various organic guest molecules by 1, e.g., substituted benzenes, alkanes, ethers, and chlorocarbons. Complex 1 is the first iron(II)-containing cage complex that is formed by assembly of resorcinarene molecules and that binds neutral organic molecules.