The rich electron correlations and highly coherent transport in reconfigurable devices sketched by a conductive atomic force microscope tip at the $\mathrm{LaAl}{\mathrm{O}}_{3}/\mathrm{SrTi}{\mathrm{O}}_{3}$ interface have enabled the oxide platform an ideal playground for studying correlated electrons and quantum technological applications. Why these one-dimensional devices possess enhanced properties over the two-dimensional interface, however, has remained elusive. Here, we provide evidence that one-dimensional $\mathrm{LaAl}{\mathrm{O}}_{3}/\mathrm{SrTi}{\mathrm{O}}_{3}$ nanowires are intrinsically ferroelastic domain walls by nature through thermodynamic study. We have observed spreading resistance anomalies under thermostimulus and temperature cycles with characteristic temperatures matching domain-wall polarity. This information is crucial in understanding the novel phenomena including superconductivity and high mobility quantum transport.