It lies in the Székely Land, a mainly Hungarian-speaking ethno-cultural region in eastern Transylvania, and is situated in the Olt River valley.

The city administers three villages: Ciba (Csiba), Harghita-Băi (Hargita-fürdő), and Jigodin-Băi (Zsögöd-fürdő), including Jigodin (Csíkzsögöd).

[4] Demographic movements according to census data: Roman Catholicism is the majority religion of Miercurea Ciuc, its adherents numbering 74.06% of the total population.

The Early Music Festival takes place every year in July, from 1980 onwards, mainly in the court of the castle.

In 2006 the ice rink hosted the world junior championship in short track speed skating.

[citation needed] Miercurea-Ciuc is home to the Baroque church at Șumuleu Ciuc and, in the city center, the Mikó Castle, built in a late Renaissance style.

The original more decorative castle was raised in the 17th century on the orders of Ferenc Mikó Hídvégi, the personal advisor of Gabriel Bethlen, then prince of Transylvania.

Much of the castle was destroyed in 1661 during the Tatar raids, but it was rebuilt at the beginning of the 18th century and was mainly used as a barracks; today it houses the Csík Székely Museum.

Behind the castle is a small Skanzen (museum village), consisting of a few traditional Csíki houses and wooden gates.

A few kilometres to the east of the city centre is the Franciscan monastery of Șumuleu Ciuc, known in Hungarian as Csíksomlyó.

A wooden-sculpture figure of the Virgin Mary, known as the Weeping Mary, can be found in the monastery church, which is the destination of a traditional pilgrimage of Roman Catholic Székely held since 1567, called the "Csíksomlyó Pilgrimage" (Romanian: Pelerinajul de la Sumuleu; Hungarian: Csíksomlyói Búcsú).

Beside its religious importance, the pilgrimage has also become a demonstration of the awareness and solidarity of Catholic Hungarian people living in and outside the historical region of Transylvania.

[13] The local council has 19 members with the UDMR holding the majority of the seats:[14] Miercurea Ciuc is twinned with: