Changes taking place in the town during the period of industrialization, especially in the 2nd half of the 19th century must have been surprising for its residents.

Planty park was opened, first street was paved, the main square was equipped with gas lamps (ca. 1867) and a new town hall which still exists today was built (ca. 1872).

Construction of hard surface roads started, and a first railway line was opened in Mikołów in mid 19th century (1856).

Two more churches were built, namely in years 1843 – 1861 the catholic parish built a new church dedicated to St. Adalbert which is now a minor basilica. In 1861 evangelicals  finished the construction of St. John church.
There was also a brick synagogue built in 1816, and until1970s it was located on what is now known as 750-lecia square.

The town also had a court, hospitals, police headquarters, post office, slaughterhouse and a prison.

High schools were first opened in Mikołów in 1870s as a result of efforts made by parents who wanted young people to complete education received  in a national school.

First, in 1873 a private high school for girls was opened. Since 1903 it was located near Planty park. From 1922 until the outbreak of World War II it functioned as a school for the German minority.
First high school for boys was opened in 1875. It functioned for 7 years only and it provided a background to those who wanted to go the secondary school and teachers college.

Another one was opened in 1904 and was called Städtische Höhere Knabenschule Nicolai (Town High School for Boys in Mikołów).

It was located at Karol Miarki Street. Transformation of the German secondary school into Polish
secondary school started in June 1922. It was the beginning of Karol Miarka High School.