Topographic corrugations, such as wrinkles, are known to introduce diverse physical phenomena that can significantly modify the electrical, optical and chemical properties of two-dimensional materials. This range of assets can be expanded even further when the crystal lattices of the walls of the wrinkle are aligned and form a superlattice, thereby creating a high aspect ratio analogue of a twisted bilayer or multilayer - the so-called twisted wrinkle. Here we present an experimental proof that such twisted wrinkles exist in graphene monolayers on the scale of several micrometres. Combining atomic force microscopy and Raman spectral mapping using a wide range of visible excitation energies, we show that the wrinkles are extremely narrow and their Raman spectra exhibit all the characteristic features of twisted bilayer or multilayer graphene. In light of a recent breakthrough - the superconductivity of a magic-angle graphene bilayer, the collapsed wrinkles represent naturally occurring systems with tuneable collective regimes.

Department of Condensed Matter Physics Faculty of Mathematics and Physics Charles University Ke Karlovu 5 121 16 Prague 2 Czech Republic

Department of Inorganic Chemistry Faculty of Science Charles University Albertov 6 128 43 Prague 2 Czech Republic

Faculty of Natural Sciences Department of Physics Norwegian University of Science and Technology Høgskoleringen 5 NO 7491 Trondheim Norway

J Heyrovsky Institute of Physical Chemistry of the CAS v v i Dolejskova 3 182 23 Prague 8 Czech Republic

Leibniz Institute of Photonic Technology PO Box 100239 D 07702 Jena Germany

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