Over the last 800 years it hasn't had much use as it was a gate that really led nowhere. The city walls had become redundant and the market-gardens and orchards were spread both without and within.
However, in the Siege during the First Crusade the site was a hotly contested one due to the existence of the bridge over the old silted up branch of the river which was nevertheless a swampy territory which filled up due to a nearby spring. This made the old channel an obstacle for the beseigers. In the excerpt below (from Dictionnaire historique, géographique et biographique des croisades by Edouard d' Ault-Dumesnil, 1852) we see that the Crusaders tried to destroy this obviously very solid structure to stop the beseiged from sallying forth and making havoc in the Crusaders camp (which must have been somewhere in the vicinity of the hippodrome/palace complex):
"Les assiégeants entreprirent aussi de rompre un pont qui ètait bàti sur un marais, en face de la porte de Chien, et par lequel les infidèles faisaient des sorties sur les troupes du comte de Toulouse. Ce pont résista par sa grande solidité à tous les efforts qui furent faits pour le démolir, et on ne trouva d'autre moyen, pour arrêter les sorties, que de construire une grande tour, où les pèlerins s'entassèrent comme des abeilles dans leur ruche, suivant l'expression de Robert le Moine. Mais les assiégés mirent le feu à cette tour, et la réduisirent en cendres. Le lendemain, les chrétiens établirent trois balistes avec lesquelles ils lancèrent des quartiers de roche. Ces machines furent encore détruites par les Turcs. Les chrétiens se décidèrent alors à trainer, à force de bras, d'énormes morceaux de rochers devant la porte même, et à les y accumuler tellement qu'il ne fût plus possible de l'ouvrir."
En Poccardi's improved street layout for the Island, he orients the Dog Gate & bridge with the east side of the hippodrome and proposes that the thoroughfare crossing the bridge was one of the four porticoed avenues that Libanius speaks of as joining at the Tetrapylon of the Elephants.
William Ainsworth in his 1842 report of his visit to the city speaks of virtually nothing except an inscription he found on the "north tower". He included the above illustration. This does not look like the Cassas' image of the outside of the Beroea Gate so we have to presume it was the Porta Canis. It would be great to confirm that it was the latter as we have no images of this structure in its original format. The depression in front could be the old riverbed of the silted up branch.
He records an inscription in Greek, which would seem to imply that this is from ancient rather than Crusader times. It reads:
This he translates as:
Sunk to ruin by time and tumult, * * * *
Medon had hastily built
With haste and difficulty the army of the * * * *
Forster in 1898 reports that the gate had been dismantled and its parts had been reused to build Ibrahim Pascha's notorious barracks (which were the ruin of many a solid Antioch surviving remnant). "Der Stein ist seitdem zersagt und zum Bau der Caserne Ibrahim Paschas verwendet worden. Ein Stuck, den Anfang der 4 Zeilen enthaltend, 0.53m lang, 0.37 hoch, befindet sich jetzt in der untersten Lage einer Freitreppe im Hofe, wo er von Renan kopiert worden ist, danach, in besserer Gestalt bei Le Bas-Waddington, Voyage archeologique, Incr.III, 1 n.2712) veroffentlich".
Therefore the inscription survived in the new structure in an obscure position but he had ferreted out its location. He also noted there was more to read than Ainsworth had found. Our colleague, Jorgen Christensen-Ernst asked his friend Ulrik Poss at the University of Copenhagen to help with the text and the latter has translated this passage as:
Χρονω κλονω τε προς φθοραν νενευκοτα (ε)ρδειν Θεος μεδων τετευχει συν ταχει σπουδηι στρατον μογω τε των οικητορων τον πυργονGod the Protector has caused an army in speed and the inhabitants with labour to build the tower that due to age and martial uproar had leaned upon its destruction
Poss comments: "I therefore still regard τετεύχει as taking an accusative with an infinitive. The I take στρατὸν as subject of ἔρδειν, τὸν πύργον as object and to it the conjunct participle νενευκότα.
I feel that this makes better sense.But still, the text is rather fragmentary".
Below can be seen a photo of the ruins of the gate taken in November 2008, looking towards Mt Silpius.