The history of the development of molecular nanocarbon science can be classified in terms of topology. Cycloparaphenylene (CPP), which was first proposed in the 1930s, is a ring-shaped molecular nanocarbon that represents a partial structure of carbon nanotubes (CNTs) . Although CPPs were initially difficult to synthesize due to their high intrinsic strain energies, several synthetic methods, such as those reported since 2008 by Jasti, Itami, and Yamago , have enabled the creation of molecular nanocarbons that exhibit nontrivial topologies, such as cages , catenanes, and knots . The next breakthrough in this research field was the synthesis of a carbon nanobelt (CNB), achieved by our group in 2017 . The fully fused, belt-shaped topology of CNBs creates two non-convertible faces, i.e., the inner and outer faces. Since then, the synthetic chemistry of CNBs and related belt-shaped arenes has been intensively investigated worldwide in the context of the bottom-up construction of CNT substructures as well as the creation of new functional molecular nanocarbon materials.