Oft to the town he turns his eyes,
Whence Dido’s fires already rise.
What cause has lit so fierce a flame
They know not: but the pangs of shame
From great love wronged, and what despair
Can make a baffled woman dare —
All this they know, and knowing tread
The paths of presage, vague and dread.

[… moenia respiciens, quae iam infelicis Elissae
conlucent flammis. Quae tantum accenderit ignem,
causa latet; duri magno sed amore dolores
polluto, notumque, furens quid femina possit,
triste per augurium Teucrorum pectora ducunt.]

Virgil the Poet
Virgil (70-19 BC) Roman poet [b. Publius Vergilius Maro; also Vergil]
The Aeneid [Ænē̆is], Book 5, l. 4ff (5.4-8) (29-19 BC) [tr. Conington (1866)]
    (Source)

Elissa is an alternate name for Dido.

(Source (Latin)). Alternate translations:

Viewing unhappy Dido's wals, which shone
With flames, the cause such fire had rais'd, unknown;
But what a woman might in sorrow drown'd,
Struck deep with grief and burning love was found;
And by sad auguries Trojans understand.
[tr. Ogilby (1649)]

Then, casting back his eyes, with dire amaze,
Sees on the Punic shore the mounting blaze.
The cause unknown; yet his presaging mind
The fate of Dido from the fire divin'd;
He knew the stormy souls of womankind,
What secret springs their eager passions move,
How capable of death for injur'd love.
Dire auguries from hence the Trojans draw;
Till neither fires nor shining shores they saw.
[tr. Dryden (1697)]

... looking back at the walls which now glare with the flames of unfortunate Elisa. What cause may have kindled such a blaze is unknown; but the thought of those cruel agonies that arise from violent love when injured, and the knowledge of what frantic woman can do, led the minds of the Trojans through dismal forebodings.
[tr. Davidson/Buckley (1854)]

He saw the city glaring with the flames
Of the unhappy Dido. What had lit
This fire, they knew not; but the cruel pangs
From outraged love, and what a woman's rage
Could do, they know; and through the Trojans' thoughts
Pass sad forebodings of the truth.
[tr. Cranch (1872)]

... looking back on the city that even now gleams with hapless Elissa's funeral flame. Why the broad blaze is lit lies unknown; but the bitter pain of a great love trampled, and the knowledge of what woman can do in madness, draw the Teucrians' hearts to gloomy guesses.
[tr. Mackail (1885)]

... Still looking back upon the walls now litten by the flame
Of hapless Dido: though indeed whence so great burning came
They knew not; but the thought of grief that comes of love defiled
How great it is, what deed may come of woman waxen wild,
Through woeful boding of the sooth the Teucrians' bosoms bore.
[tr. Morris (1900)]

... And backward on the city bent his gaze,
Bright with the flames of Dido. Whence the blaze
Arose, they knew not; but the pangs they knew
When love is passionate, and man betrays,
And what a frantic woman scorned can do,
And many a sad surmise their boding thoughts pursue
[tr. Taylor (1907)]

         ... but when his eyes
looked back on Carthage, they beheld the glare
of hapless Dido's fire. Not yet was known
what kindled the wild flames; but that the pang
of outraged love is cruel, and what the heart
of desperate woman dares, they knew too well,
and sad foreboding shook each Trojan soul.
[tr. Williams (1910)]

... looking back on the city walls which now gleam with unhappy Elissa's funeral flames. What cause kindled so great a flame is unknown; but the cruel pangs when deep love is profaned, and knowledge of what a woman can do in frenzy, lead the hearts of the Trojans amid sad forebodings.
[tr. Fairclough (1916)]

         His gaze went back
To the walls of Carthage, glowing in the flame
Of Dido’s funeral pyre. What cause had kindled
So high a blaze, they did not know, but anguish
When love is wounded deep, and the way of a woman
With frenzy in her heart, they knew too well,
And dwelt on with foreboding.
[tr. Humphries (1951)]

He looked back at Carthage's walls; they were lit up now by the death-fires
Of tragic Dido. Why so big a fire should be burning
Was a mystery: but knowing what a woman is capable of
When insane with the grief of having her love cruelly dishonoured
Started a train of uneasy conjecture in the Trojans' minds.
[tr. Day-Lewis (1952)]

         ... gazing
back -- watching where the walls of Carthage glowed
with sad Elissa's flames. They cannot know
what caused so vast a blaze, and yet the Trojans
know well the pain when passion is profaned
and how a woman driven wild can act;
their hearts are drawn through dark presentiments.
[tr. Mandelbaum (1971)]

         But he kept his eyes
Upon the city far astern, now bright
With poor Elissa's pyre. What caused that blaze
Remained unknown to watchers out at sea,
But what they knew of a great love profaned
In anguish, and a desperate woman's nerve,
Led every Trojan heart into foreboding.
[tr. Fitzgerald (1981)]

... looking back at the walls of Carthage, glowing now in the flames of poor Dido's pyre. No one understood what had lit such a blaze, but since they all knew what bitter suffering is caused when a great love is desecrated and what a woman is capable when driven to madness, the minds of the Trojans were filled with dark foreboding.
[tr. West (1990)]

... looking back at the city walls that were glowing now with
unhappy Dido’s funeral flames. The reason that such a fire had
been lit was unknown: but the cruel pain when a great love is
profaned, and the knowledge of what a frenzied woman might do,
drove the minds of the Trojans to sombre forebodings.
[tr. Kline (2002)]

... he glanced back at the walls of Carthage
set aglow by the fires of tragic Dido’s pyre.
What could light such a conflagration? A mystery --
but the Trojans know the pains of a great love
defiled, and the lengths a woman driven mad can go,
and it leads their hearts down ways of grim foreboding.
[tr. Fagles (2006)]

... gazing back at city walls lit up by the flames -- poor Dido's pyre. No one knew what caused the blaze, but they knew the great grief of a love betrayed and what a woman's passion could unleash. Their hearts were somber with foreboding.
[tr. Bartsch (2021)]