Bound nuclear systems with two units of strangeness are still poorly known despite their importance for many strong interaction phenomena. Stored antiprotons beams in the GeV range represent an unparalleled factory for various hyperon–antihyperon pairs. Their outstanding large production probability in antiproton collisions will open the floodgates for a series of new studies of systems which contain two or even more units of strangeness at the f&_user=111111111&_pii=S0375947416301282&_rdoc=1&_issn=03759474&md5=ed69779762a62e4ddc2636a827477683">f" data-inlimgeid="1-s2.0-S0375947416301282-si1.gif"> experiment at FAIR. For the first time, high resolution γ -spectroscopy of doubly strange ΛΛ-hypernuclei will be performed, thus complementing measurements of ground state decays of ΛΛ-hypernuclei at J-PARC or possible decays of particle unstable hypernuclei in heavy ion reactions. High resolution spectroscopy of multistrange formulatext stixSupport mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S0375947416301282&_mathId=si2.gif&_user=111111111&_pii=S0375947416301282&_rdoc=1&_issn=03759474&md5=839b3f23d2d8fe329bb4f30b1fa809d4" title="Click to view the MathML source">Ξ−-atoms will be feasible and even the production of formulatext stixSupport mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S0375947416301282&_mathId=si3.gif&_user=111111111&_pii=S0375947416301282&_rdoc=1&_issn=03759474&md5=b9f7e0be5ad6b160d462899822a101c8" title="Click to view the MathML source">Ω−-atoms will be within reach. The latter might open the door to the formulatext stixSupport mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S0375947416301282&_mathId=si4.gif&_user=111111111&_pii=S0375947416301282&_rdoc=1&_issn=03759474&md5=485554f5f4d3a1eef964498c8e64be76" title="Click to view the MathML source">|S|=3 world in strangeness nuclear physics, by the study of the hadronic formulatext stixSupport mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S0375947416301282&_mathId=si3.gif&_user=111111111&_pii=S0375947416301282&_rdoc=1&_issn=03759474&md5=b9f7e0be5ad6b160d462899822a101c8" title="Click to view the MathML source">Ω−-nucleus interaction. For the first time it will be possible to study the behavior of f&_user=111111111&_pii=S0375947416301282&_rdoc=1&_issn=03759474&md5=8f1fa260e67fd541a605a40c615e4aab">f" data-inlimgeid="1-s2.0-S0375947416301282-si5.gif"> in nuclear systems under well controlled conditions.