The Georges graph, also called the Georges-Kel'mans graph, is the 50-node graph illustrated above that is the smallest 3-connected bicubic nonhamiltonian graph. It was independently discovered by Georges (1989) and Kelmans (1988) as the smallest known such example. It was subsequently proved to be the smallest possible by Brinkmann et al. (2022).
It is implemented in the Wolfram Language as GraphData["GeorgesGraph"].
The original embedding showing the construction is illustrated above (Grünbaum 2006).