BL-1A is dedicated to microcrystallography and long wavelength SAD (Single Anomalous dispersion) experiments. The beamline is designed to take full advantage of a long wavelengh X-ray beam at around 3 A to further enhance anomalous signals. The light source is an in-vacuum short gap undulator optimized at around the wavelength with the fundamental harmonics to obtain maximum brilliance. The vacuum section of the beamline has only one terminal beryllium window, followed by a diffractometer equipped with a helium cryostream and a specially designed helium chamber to minimize the attenuation of the lower energy beam and background noises. A cryo-cooled channel-cut monochromator and bimorph KB focusing mirrors compose a simple optics to deliver a focused beam with a good stability.