I think there's a temple to some goddess in the vicinity of Tirupati that was established by Vishnu himself. Let me explain.
As I discuss in this question, the book "Venkatachala - Its Glory" by G.V. Chalapathi Rao is an English translation of the Sthala Purana (temple scripture) of the famous Tirupati temple and this temple scripture consists of excerpts from various Puranas that discuss the story of Venkateshwara (the Vishnu deity in Tirupati, AKA Srinivasa or Balaji).
The Purana describes the wedding of Vishnu and Padmavathi in great detail. Before the wedding begins, the god Brahma, who is officiating the wedding, asks Vishnu to go worship his "family deity". This excerpt describes what Vishnu does in response:
"Our family deity is the sacred Sami tree" said Srinivasa. Agastya located the tree. The bridegroom went round it praising it. He then offered worship to his family goddess.... In a golden vessel, filled with pearls and covered by a costly cloth, the family goddess was offered worship and consecrated near Lord Varaha. Srinivasa was conducting himself as an ordinary human being!
I already asked a question here about why the Sami tree is sacred to Vishnu, but now I'm wondering, who is Vishnu's "family goddess", whom Vishnu worships after worshipping the Sami tree? The only clue we have is that fact that Vishnu apparently had a statue of this goddess "consecrated near Lord Varaha." Let me explain what that means.
Most people only know the story of Vishnu's incarnation as Varaha the boar up to the part where he defeats the demon Hiranyaksha and rescues the earth from the water. But as I discuss in this answer, afterwards he came down and started living on the Earth for the benefit of his devotees, and in fact Varaha is still alive to this day, on the western bank of the Swamipushkarini lake near Tirupati. (In fact the original name of the Tirupati area is Adi Varaha Kshetra - the place of the first Varaha.) Since Varaha lives there, a temple was built there in his honor, the great Varaha Swami Temple. Devotees of the Tirumala Venkateshwara Temple in Tirupati, located on the southern bank of Swamipushkarini, are supposed to first worship Varaha in the western bank.
So are there any temples to goddesses in the vicinity of the Varaha Swami temple? You'd expect that people would take great pains to preserve a temple established by Vishnu himself, so hopefully it still exists today.