The claustrum is an irregular and fine sheet of grey matter in the basolateral telencephalon present in almost all mammals. The claustrum has been the object of several studies using animal models and more recently in human beings using neuroimaging. It has been involved in cognition and disease such as fear recognition, suppression of natural urges, multisensory integration, conceptual integration, seizures, multiple sclerosis and Parkinsons disease. Nevertheless, the function of the claustrum still remains unclear. We present a high resolution functional connectivity study of the claustrum in order to identify its main networks. Resting state functional and anatomical MRI data from 40 healthy subjects were analyzed; taken from the Human Connectome Project (HCP, NIH Bleuprint: The Human Connectome Project), with 2x2x2 mm3 voxel resolution, equivalent to the high resolution tractography studies. Positive functional connectivity was found (p<0.05, FDR corrected) between the claustrum and the insula, anterior cingulate cortex, pre-central and postcentral gyrus, superior temporal gyrus and subcortical areas. Our findings coincide with the results previously reported in both animal models and studies with humans. Showing the claustrum as a profusely connected structure not only structurally but also functionally. Evidencing the claustrum as a node participating in a plethora neural networks.