An optical routing mechanism is provided that may be used in a wavelength router configured to receive light having multiple spectral bands from an input fiber and to direct subsets of the spectral bands to respective output fibers. A free-space optical train provides optical paths for routing the spectral bands between the input fiber and the output fibers. The optical routing mechanism has multiple configurable routing elements to determine how each spectral band is directed. A common surface integrally mates the optical routing mechanism with end portions of the input and output fibers, permitting effective planarization of some optical elements.