In the old town centre we can see the St. Ahacij Square with the baroque fountain, where was discovered rich mercury ore, mining theatre and mining magazine, Town Hall and Lace School Idrija in the Town Square, Franciska's Shaft, Church of the Holy Trinity, first Secondary School, Scopoli's House, who was the first Idrija's medicine doctor, Miner's House, chapel, public aquarium and much more. Old town centre Idrija has beside the oldest St. Ahacij Square, newest Town Square, also the Scopoli Square and Aumeski Square, which is named by the French cist Aumetz, which is twinned with Idrija.
Lace School Idrija is responsible for preserving the knowledge of many elements and techniques of lace making. Idrija is also known for its local food speciality called idrijski zlikrofi, which is prepared from dough and stuffed with special potato stuffing and hand made. Idrija's mining band is one with the longest tradition in Slovenia. Above the old town centre proudly raises the Castle Gewerkenegg, which was built in the 16th century and was for centuries the seat of the mining administration and place for storage of mercury. Here was a center of trade of mercury in Idrija.
Today is the castle seat of the Municipal Museum Idrija with its permanent exhibition named Five centuries of the mercury mine and the town of Idrija. On a hill above Idrija is the Church of St. Anthony with Calvary and from here is a beautiful view to the newest part of the town and surroundings.