Roma Aeterna cap XXXVI

Having spent about two years on Familia Romana – which included a few false starts and some serious revision over the last couple of months – I decided it’s time to move on to Roma Aeterna. However, struggling to make sense of the following phrase I wonder if that’s the right decision or whether it’s time to call it a day – and take up knitting.

RA XXXVI, top of p. 13:
Ex aedibus sacrīs (Abl.pl.) forī Rōmānī (Gen.singl.) minima quidem, sed veterrima est aedēs Iānī quae ad infimum Argilētum sita est.

Minima: superlative, f. nom. sing. Or n. nom/acc. pl.

Completely stuck over “minima quidem”.

I expected “sunt”, i.e. quidem aedibus sacris fori Romani minima sunt, sed . . .

Maybe this paraphrase helps:

Ex omnibus aedibus quae in foro Romano sunt, minima et veterrima est aedes (nom. sg. f.) Iani (gen. sg. m.).

ita - gratias tibi ago