Magic-angle graphene superlattices have been shown to host intrinsic unconventional superconductivity. By twisting two graphene layers at a small angle, particularly near 1.1 degrees, a flat band structure is formed, leading to correlated insulating states at half-filling. Upon electrostatic doping away from these states, tunable zero-resistance states with a critical temperature up to 1.7 K are observed. The temperature-density phase diagram of this system resembles that of cuprates, including superconducting domes. Quantum oscillations indicate small Fermi surfaces near the correlated insulating phase, similar to under-doped cuprates. The relatively high Tc for such small Fermi surface suggests that twisted bilayer graphene (TBG) is among the strongest coupling superconductors, in a regime close to the BCS-BEC crossover. These results establish TBG as the first purely carbon-based 2D superconductor and as a highly tunable platform for studying strongly-correlated phenomena, which could lead to insights into the physics of high-Tc superconductors and quantum spin liquids. The superconductivity in TBG is observed in a 2D superlattice made from graphene, known as Magic Angle Twisted Bilayer Graphene (MA-TBG). This system allows for in situ electrical tunability of the charge carrier density in ultra-flat bands, enabling the study of the phase diagram of unconventional superconductivity with unprecedented resolution. The observed superconductivity shows features similar to cuprates, including dome structures in the phase diagram and quantum oscillations that point towards small Fermi surfaces near a correlated insulator state. The superconductivity occurs for record-low carrier densities, orders of magnitude lower than typical 2D superconductors. The relatively high Tc for such small densities puts MA-TBG among the strongest coupling superconductors, in the same league as cuprates and recently identified FeSe thin layers. The results also establish MA-TBG as the first purely carbon-based 2D superconductor and as a relatively simple and highly tunable platform that enables thorough investigation of strongly correlated physics.Magic-angle graphene superlattices have been shown to host intrinsic unconventional superconductivity. By twisting two graphene layers at a small angle, particularly near 1.1 degrees, a flat band structure is formed, leading to correlated insulating states at half-filling. Upon electrostatic doping away from these states, tunable zero-resistance states with a critical temperature up to 1.7 K are observed. The temperature-density phase diagram of this system resembles that of cuprates, including superconducting domes. Quantum oscillations indicate small Fermi surfaces near the correlated insulating phase, similar to under-doped cuprates. The relatively high Tc for such small Fermi surface suggests that twisted bilayer graphene (TBG) is among the strongest coupling superconductors, in a regime close to the BCS-BEC crossover. These results establish TBG as the first purely carbon-based 2D superconductor and as a highly tunable platform for studying strongly-correlated phenomena, which could lead to insights into the physics of high-Tc superconductors and quantum spin liquids. The superconductivity in TBG is observed in a 2D superlattice made from graphene, known as Magic Angle Twisted Bilayer Graphene (MA-TBG). This system allows for in situ electrical tunability of the charge carrier density in ultra-flat bands, enabling the study of the phase diagram of unconventional superconductivity with unprecedented resolution. The observed superconductivity shows features similar to cuprates, including dome structures in the phase diagram and quantum oscillations that point towards small Fermi surfaces near a correlated insulator state. The superconductivity occurs for record-low carrier densities, orders of magnitude lower than typical 2D superconductors. The relatively high Tc for such small densities puts MA-TBG among the strongest coupling superconductors, in the same league as cuprates and recently identified FeSe thin layers. The results also establish MA-TBG as the first purely carbon-based 2D superconductor and as a relatively simple and highly tunable platform that enables thorough investigation of strongly correlated physics.