This study is a multidisciplinary contribution to the thermochemistry of 1,4-cubanedicarboxylic acid (pentacyclo[4.2.0.0(2,5).0(3,8).0(4,7)]octane-1,4-dicarboxylic acid). An isoperibolic static microbomb calorimeter was used to determine the enthalpy of formation in the condensed phase at T = 298.15 K as Delta(f)H(m)(circle),(cr) = (-355.9 +/- 11.7) kJ.mol(-1). The enthalpy of sublimation was obtained by combining the vaporization enthalpy evaluated by correlation-gas chromatography and the fusion enthalpy measured by differential scanning calorimetry and adjusted to T = 298.15 K, which afforded the value Delta(sub)H(m),(298.15 K) = (126.5 +/- 9.0) kJ.mol(-1). Combination of these two enthalpies gave Delta(f)H(m)(circle)(g, 298.15 K) = (-229.4 +/- 14.8) kJ.mol(-1). Additionally the enthalpy of sublimation of 1-adamantanecarboxylic acid (tricyclo [3.3.1.1(3,7)] decane-1-carboxylic acid) was determined as A, 1,H,,(298.15 = (98.7 +/- 4.5) kJ.mol(-1). By means of theoretical calculations using isodesmic reactions, the enthalpy of formation of 2,6-cuneanedicarboxylic acid (pentacyclo[3.3.0.0(2,4).0(3,7).0(6,8)]octane-2,6-dicarboxylic acid) was calculated. Strain energies of cubane and cuneane dicarboxylic acids were also calculated.