Dengan diameter mencapai 23 menit busur, M13 dapat terlihat dengan teleskop kecil. Di dekatnya ada NGC 6207, galaksi tepi magnitudo ke-12 yang terletak 28 menit busar lurus ke timur laut.
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^Paust, Nathaniel E. Q.; et al. (2010), "The ACS Survey of Galactic Globular Clusters. VIII. Effects of Environment on Globular Cluster Global Mass Functions", The Astronomical Journal, 139 (2): 476–491, Bibcode:2010AJ....139..476P, doi:10.1088/0004-6256/139/2/476.