The Wiman-Edge pencil is the universal family C t , t ∈ B of projective, genus 6, complex-algebraic curves admitting a faithful action of the icosahedral group A 5 . The curve C 0 , discovered by Wiman in 1895 [11] and called the Wiman curve, is the unique smooth, genus 6 curve admitting a faithful action of the symmetric group S 5 . In this paper we give an explicit uniformization of B as a non-congruence quotient Γ\H of the hyperbolic plane H, where Γ < PSL 2 (Z) is a subgroup of index 18. We also give modular interpretations for various aspects of this uniformization, for example for the degenerations of C t into 10 lines (resp. 5 conics) whose intersection graph is the Petersen graph (resp. K 5 ).In the second half of this paper we give an explicit arithmetic uniformization of the Wiman curve C 0 itself as the quotient Λ\H, where Λ is a principal level 5 subgroup of a certain "unit spinor norm" group of Möbius transformations. We then prove that C 0 is a certain moduli space of Hodge structures, endowing it with the structure of a Shimura curve of indefinite quaternionic type.