Mirandela Castle occupies most of the old town, ordered to be built by King D. Dinis, at the end of the 13th century, for Cabeço de S. Miguel, corresponding to the place where the Church of Nª Srªda Encarnaçión and Pazo dos Távoras (Town Hall) were located, since the place was very defensible, overlooking the river and cut by not very gentle and even rough slopes, being walled, making it a stronghold in the style of the time. .

Military activity continued until the end of the wars with Castile, after the victory of Aljubarrota, after which the castle began to decline, losing its reason for being as it was not a border town.

Mirandela Castle had a wall, four gates: Santo António Gate, Santiago Gate, Portela Gate and São José Gate.

In front of the Santo António gate, which could only be entered on foot from inside the wall, as the street was very steep, and for those who crossed the river by boat, since at that time there was no bridge, there was about 15 meters towards the river, a section of masonry wall, also with a complete arched gate, which was not exactly in the extension of the Rúa do Arco, but slightly to the left of it, and which would be the remains of the Old Barbican (wall built in front of the walls and lower than them), intended to defend the gate, in the case of Santo António.

Next to the castle or keep, more or less on the current site of the Pazo dos Távoras, there would probably also be the citadel (house designed and built for the royal retreat).

References to the decline of the monument were accentuated in modern times and, in 1706, Carvalho da Costa also mentions the existence of three gates: Porta or Arco de Santiago; Porta de Santo António and Postigo de São José. The 19th century was particularly detrimental to the survival of the castle. At this time, under the idea of ​​”progress”, many Portuguese towns and villages saw their walls torn down, and Mirandela, unfortunately, was no exception.

The last gate destroyed was the Santiago gate, opposite the Solar Condes de Vinhais and exit to the north of the Praça Velha (Praça 5 de Outubro) and which gave rise to the street of the same name, demolished in 1880, when it was alleged that the narrowing of the gate made it difficult for freight vehicles to pass.

What is visible today is the Porta de Santo António and a small section of wall that runs into the building that borders it to the north, today Pensão Praia, and also two sections of wall visible at the beginning of rue do Rosário and at the confluence. with Rua de S. José (site of the old S. José Gate).

Virtually all the rear walls of the buildings bordering Rua Luciano Cordeiro and Rua S. Cosme are still the original walls of the castle, and it is a pity that in the 1990s a section of wall of about 30 metres was destroyed to build buildings (Casa Lima lands, on Rua Luciano Cordeiro and junction with Rua D. Manuel I).

There are still vestiges of Rua da Muralha found in the context of archaeological works carried out on Travessa de Santo António.

It was classified as a Public Interest Property in 1955.