%A Singerman, David %A Strudwick, James %D 2019 %T The Farey maps modulo n %K %X Let $U^{\star}$ denote the upper-half plane compactified by adding the points $Q \cup {\infty}$ to the upper half plane $U$ . On $U$ we have the universal triangular map $M_3$ which can be realised by the well-known Farey map as described below. These have as vertices the extended rationals $Q \cup {\infty}$. Our aim in this paper is to discuss the maps (or clean dessin d’enfants) $M_3=/\Gamma(n)$ which lies on the Riemann surface $U^{\star}/\Gamma (n)$ where $\Gamma (n)$ is the principal congruence subgroup mod n of the classical modular group $\Gamma$. These have vertices as rational numbers "modulo $n$". These were introduced in [4] and also discussed in [8]. %U http://www.iam.fmph.uniba.sk/amuc/ojs/index.php/amuc/article/view/913 %J Acta Mathematica Universitatis Comenianae %0 Journal Article %P 39-52%V 89 %N 1 %@ 0862-9544 %8 2019-10-21