The solution self-assembly of trans-{EuI2} nodes and ditopic pyrazine or 4,4'-bipyridine leads to isoreticular 2D frameworks featuring the rare elongated triangular Archimedean tessellation pattern. The topology and the presence of intra-layer Eu(II)-Eu(II) antiferromagnetic interactions provide the prerequisites for geometrical spin frustration, which, due to the spin ground state degeneracy, is key for exotic magnetic phenomena such as enhanced magnetic refrigeration.