Maupertuis est un cratère délabré de 46 Km situé sur un contrefort continental entourant le Golfe des Iris (Sinus Iridum). Au sud de Maupertuis on trouve le célèbre promontoire Laplace. Maupertuis est de forme irrégulière, avec des murailles abîmées plus élevées sur les murs Est et Sud. Le fond est tourmenté par de nombreuses lignes de crête orientées Sud-ouest vers le Nord-Est.

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Maupertius is the remnant of a lunar crater that is located in the northern part of the Moon's near side. It lies in the stretch of rugged terrain north of Sinus Iridum, a bay in the northwestern corner of the Mare Imbrium. To the north lies La Condamine crater and Mare Frigoris.
This is a crater that has been nearly obliterated by a history of impacts, leaving only a disintegrated remnant of the original rim. The surviving outer rim is not especially circular, having been reshaped into a somewhat pentagonal outline. There are deep gouges from cratering along the northeastern rim. The interior floor is not in much better shape, being rough and irregular.
To the northeast of this crater is a system of rilles that have the designation Rimae Maupertius. These are considered to have formed through geological activity. The rilles require good seeing and a larger telescope to observe.