Liebfrauenkirche, Trier

Listen for a moment. Step inside and the sound changes. The noise of the square fades behind the heavy doors, and a cool, stony quiet takes its place. Your footsteps carry upward, into a space that seems to open in every direction at once. Look up, then turn slowly on the spot. Something here feels different from almost any church you have visited before.

You are standing in the Liebfrauenkirche, the Church of Our Lady, in Trier. It sits right beside the cathedral, so close that the two buildings almost touch. Many visitors pass through it in a few minutes on their way somewhere else. That is a pity. This is one of the earliest Gothic churches in Germany, and it was a bold experiment in its day. It began in the thirteenth century, when Gothic building was still new east of the Rhine.

First, a quick word on Gothic. It is the style that began in France in the twelfth century. Pointed arches, ribbed vaults and large windows allowed walls to become thinner and buildings to fill with light. Germany at that time still built mostly in the heavier Romanesque style, with round arches and thick walls. When this church went up, it was close to the cutting edge. Scholars often link its design to French builders, and the cathedral of Reims is the name most often mentioned.

Now, back to that feeling of turning on the spot. Most medieval churches are long. You walk from the door toward the altar in a straight line. This church is different. It is built around a centre, like a cross with arms of equal length, and the corners between the arms are filled with small chapels. From above, the plan looks a little like a flower. Many people compare it to a rose with twelve petals.

That number, twelve, is the key to the whole building. The vaults rest on twelve main pillars. Medieval Christians read meaning into numbers, and twelve pointed directly to the twelve apostles, the first followers of Christ. Look closely at the pillars. On them you will see painted figures of the apostles, added long after the church was built. The idea is simple and old: the apostles are the columns that hold up the Church.

Here is a detail many visitors miss. Somewhere near the centre of the floor, people look for a spot from which all twelve apostle pillars can be seen at once. Try it yourself. Walk slowly, watch the pillars, and stop when every one of them comes into view. It is a quiet game, but it shows how carefully the builders thought about the space. The building is designed to be read from its middle.

Now look upward to the crossing, where the four arms meet. The vault here rises higher than the rest, and a tower stands above it on the outside. Light falls from many sides, through tall, narrow windows. Much of the glass you see today is modern. The church suffered heavy damage in the Second World War, like much of Trier, and later craftsmen restored it and filled the windows again.

The second surprise lies under your feet, in a historical sense. This ground has been sacred for a very long time. In the fourth century, Trier was one of the great cities of the late Roman Empire. Emperors lived here. On this site stood part of a large early Christian church complex, often linked with the age of the emperor Constantine. The cathedral next door and this church both grew on that ancient foundation.

That long story is why this church shares a place on the UNESCO World Heritage list. Since 1986, Trier's Roman monuments, the cathedral and the Church of Our Lady have been listed together. So, within one short walk, you can move from Roman stone to Romanesque towers to early Gothic vaults. Few places in northern Europe let you see these layers side by side so easily.

Before you leave, give the main portal some time. It faces the small square in front of the church. Above the door, carved figures crowd around the arch, and the Virgin Mary sits at the centre, since the church is dedicated to her. The stone has weathered over the centuries. Several of the sculptures you see outside are copies. The more fragile originals have been moved indoors, where they are safer from rain, frost and city air.

Notice too how the two churches meet. The cathedral is heavy, dark and fortress-like, with walls built over many centuries. The Church of Our Lady is lighter, taller in its proportions, and more unified, because it was planned largely as one design. The two buildings are joined by passages and a cloister. Walking between them feels like stepping from one way of thinking about God and stone into another.

This church is also a working place of worship, not only a monument. Mass is still held here, and people still come to sit quietly, light a candle, or pray. You may hear an organ practising, or the soft murmur of a small group. If a service is underway, it is best to stay at the back and keep your voice low. The building was made for this kind of stillness.

So, before you walk back out into the square, stand once more near the centre. Let your eyes travel from pillar to pillar, all the way around. Twelve columns, twelve painted faces, one open space. When you step outside, look back at the outline of the church against the cathedral. You will see the shape of that flower in the walls — now that you know it is there.