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The two eyes’ input into primate V1 is topographically organized into ocular dominance columns (ODCs). A few fMRI studies have shown the existence of ocular dominance maps in human V1, but only in a small subset of subjects with a flat V1 and using highly anisotropic ‘pencil’voxels (Cheng et al., 2001 and Yacoub et al., 2007). Here, we report robust detection of ocular dominance columns using isotropic submillimeter voxels in the same subject, at two different 7 Tesla MRI sites separated by 7,815 km. We used gradient echo EPI (0.7 mm 3dEPI and 0.8 mm 2dEPI) on a Philips Achieva 7T scanner at the Spinoza Centre in Amsterdam and a Siemens 7T Magnetom at the Institute of Biophysics of the Chinese Academy of Sciences in Beijing. Using custom-built projection screens inside the transmit coil and prism glasses for dichoptic stimulus presentation, the subject was presented monocular counterphase …