The Collegiate Church of St Servatius is a prime example of Romanesque architecture. The Romanesque style describes the architecture of Europe that emerged during the dark ages and lasted until the late tenth century, when it evolved into the Gothic style during the twelfth century. It can also be referred to as Norman architecture in England.
Romanesque appears to be a continuation of the Roman tradition of building. The style was identifiable Medieval and did not yet entail the Gothic, but maintained the rounded Roman arch along with several other distinguishable characteristics.
Romanesque architecture is characterized by its thick walls, round arches, sturdy piers (to support arches), large towers, and decorative arcading. Buildings typically have clearly defined forms and often have regular and symmetrical plans. These characteristics and more are visible in the Collegiate Church of St Servatius.
Notable characteristics of the Romanesque style reflected in the church walls, arches and openings, buttresses, towers, and murals.
Walls
Side of church
The church has walls that are massively thick with few openings. Building material differs across Europe, depending upon the local stone and building traditions.
Arches and Openings
In Romanesque architecture, arches are semicircular. Small windows adorn the buildings, usually in a semicircle shape as well. Doorways are also typically enclosed by a semi-circle arch.
Arched entrance
View of semicircular windows
Buttresses
Buttresses in Romanesque architecture are not a highly significant feature as they are in Gothic architecture because of the massive nature of Romanesque walls. Romanesque buttresses are generally of flat square profile and do not go much higher above the wall. 
Towers
Towers were an important feature of Romanesque architecture, specifically churches, and many are still standing today. They take a variety of shapes. Depending on the country, a different number of towers may be common. In Germany, four towers recently occur with spires that are four or eight sided. On the Collegiate Church of St Servatius, two towers are present with four-sided spires.
