The Aeneid by Virgil Book 1 Page 20

for his people shall set up laws and city walls, till the third summer has seen him reigning in Latium and three winters have passed in camp since the Rutulians were laid low.

But the lad Ascanius, now surnamed Iulus – Ilus he was, while the Ilian state stood firm in sovereignty – shall fulfil in empire thirty great circles of rolling months, shall ships his throne from Lavinium’s seat, and, great in power, shall build the walls of Alba Longa. Here then for thrice a hundred years unbroken shall the kingdom endure under Hector’s race, until Ilia, a royal priestess, shall bear to Mars her twin offspring. Then Romulus, proud in the tawny hide of the she-wolf, his nurse, shall take up the line, and found the walls of Mars and call the people Romans after his own name. For these I set no bounds in space