The Iglesia de las Santas Justa y Rufina is a medieval church in Toledo, Castile-La Mancha, Spain.
It is one of a group of so-called Mozarabic parish churches in Toledo, whose existence has been documented since 1156. However, certain material remains reveal the existence in this place of an Islamic construction, which would undoubtedly have to be identified with a mosque. Until very recently, the only testimony of the existence of an Islamic construction consisted of a fragment of arch that, on a Visigothic pilaster, was embedded in the northwest facade of the temple. The reuse of a piece from previous period, combined with the characteristics of the cutting of the arch, allow them to think of an Islamic work dating around 10th century.
Wikipedia https://en.wikipedia.org/wiki/Iglesia_de_las_Santas_Justa_y_Rufina,_Toledo
Address 3 Calle de Santa Justa, Toledo 45001, Spain
Coordinates 39°51'32.084" N -4°1'23.57" E