Although H⁺ has the largest hydration enthalpy among all the monovalent cations, we have demonstrated that anhydrous H⁺ can be crystallized together with selected diamidebuilding block (L) and NO₃ ^– even in acidic aqueous solutions, which were confirmed in three different structures. One of these anhydrous H⁺ adducts constitutes of H⁺-involved hydrogen-bond polymers [L···H⁺]n, which are coupled with another H⁺ adduct [O₂NO^–···H⁺···O^–NO₂]⁻ as a counteranion unit. The anhydrous H⁺ can also be trapped between L and NO₃ ^– to form heteroleptic O···H⁺···O hydrogen bonds observed in two different crystal structures. DFT calculations revealed that there is no energetic barrier in these O···H⁺···O hydrogen bonds, having so-called a single-well hydrogen bond.