Lac d'Aydat is a lake in Aydat, Puy-de-Dôme, France. At an elevation of , its surface area is . It is suggested by some historians that it is the site of Avitacum, the location of the villa belonging to the fifth-century senator and bishop Sidonius Apollinaris, as described in detail in one of his letters.Epistulae II.2 as discussed in C. E. Stevens (1933) Sidonius Apollinaris and his Age Oxford: Clarendon Press, Appendix B, p. 185.

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