Magnetic Particle Imaging (MPI) is a novel, high-contrast, and quantitative imaging modality that directly detects superparamagnetic iron oxide nanoparticle (SPIO) tracers. In MPI, the imaging sensitive region is a field free region produced by a strong gradient selection field. There are two imaging formats in MPI: Field Free Point (FFP) and Field Free Line (FFL). The spatial resolution of our previous FFL imager was limited by the strength of the FFL gradient (2.35 T/m). Here we describe the hardware development of a high resolution 6.3 T/m FFL MPI system using water-cooled electromagnets and a laminated iron-core.