It is very difficult to decide which period in the town's history should be placed under the heading of "Old Zagreb", which was made popular by Djuro Szabo, the admirer of the Zagreb antiquities and the promoter of their conservation. Zagreb's origins go back into the distant past and are enveloped in the mists of legend since there are no extant manuscripts or sufficient archaeological finds from those times. It would be much easier, therefore, to take a short walk and look at Zagreb's history. In that case Old Zagreb is represented by two settlements situated on two neighboring hills: Gradec (the Upper Town) and Kaptol, with the houses lying in the valley between them along the former Medvescak Stream (today's Tkalciceva Street) and those at the beginning of VIaska Street beneath the bishopric (later archbishopric).

Although most buildings in this area do not originate from the Middle Ages, but from the 18th century, they nevertheless display the continuity of medieval urban settlements. The existence of Kaptol, the settlement on the east slope, was confirmed in 1094 when King Ladislav founded the Zagreb bishopric. The bishop, his residence and the Cathedral had their seat in the southeast part of the Kaptol hill. VIaska Ves situated in the close vicinity of the Cathedral and under the bishop's jurisdiction was first mentioned in 1198. Kaptol Street ran from the south to the north across the Kaptol terrace with canons' residences arranged in rows alongside. As the Latin word for a group or body of canons is "capitulum" (kaptol), it is clear how Kaptol got its name. The canons also ruled this settlement.

The Cathedral was consecrated in 1217, but later in 1242 it was badly damaged by the Tartar raids. After 1263 it was restored and rebuilt. As a settlement, Kaptol was an unsymmetrical rectangle which was entered at its south end in Bakaceva Street, and existed at its north end near the present day Kaptol School. In the Middle Ages Kaptol had no fortifications; it was merely enclosed with wooden fences or palisades which had been recurrently destroyed and rebuilt. The defensive walls and towers around Kaptol were built between 1469 and 1473. The Prislin Tower near the Kaptol School is one of the best-preserved from those times. In 1493 the Turks reached Sisak trying to capture it but were defeated there.

Therefore, fearing the Turkish invasion, the Bishop of Zagreb had the fortifications built around the Cathedral and his residence. The defensive towers and walls built between 1512 and 1520 have been preserved until the present day except those which were directly facing the front of the Cathedral situated at Kaptol Square. This section of the wall was pulled down in 1907. In the 13th century two Gothic churches were built in Kaptol, St. Francis with the Franciscan monastery and St. Maria's which underwent considerable reconstruction works in the 17th and the 18th centuries. In Opatovina small dwelling houses of former Kaptol inhabitants can still be seen, but at Dolac a number of little and narrow streets were pulled down in 1926 when the market place started to be built. In 1334 the canons of Zagreb established a colony of Kaptol serfs in the vicinity of their residences, north of Kaptol; that was the beginning of a new settlement called Nova Ves (the present day Nova Ves Street).

The other part of the Old Zagreb nucleus, Gradec on the Upper Town hill, was given a royal charter by King Bela in 1242. The royal charter, also called the Golden Bull, was a very important document by which Gradec was declared and proclaimed "a free royal city on Gradec, the hill of Zagreb". This act made Gradec a feudal holding responsible directly to the king. The citizens were given rights of different kinds; among other things they were entitled to elect their own "City Judge" (the mayor) and to manage their own affairs. The citizens engaged themselves in building defensive walls and towers around their settlement, fearing a new Tartar invasion. They fulfilled their obligation between 1242 and 1261. It could be rightly assumed that by building its fortification walls in the middle of the 13th century, Gradec acquired its outward appearance that can be clearly seen in today's Upper Town.

The defensive walls enclosed the settlement in the shape of a triangle, its top located near the tower called Popov Toranj and its base at the south end (the Strossmayer Promenade), which could be explained by the shape of the hill. In some places, rectangular and semicircular towers fortified the defensive walls. There were four main gates leading to the town: the Mesnicka Gate in the west, the new, later Opaticka Gate in the north, Dverce in the south and the Stone Gate in the east. The Stone Gate is the only one preserved until the present day.

Undoubtedly, the focal point of the Upper Town is the square around St. Mark's Church that had been called St. Mark's Square for years. St. Mark's Church is the parish church of Old Zagreb. The Romanesque window found in its south facade is the best evidence that the church must have been built as early as the 13th century as is also the semicircular groundplan of St. Mary's chapel (later altered). In the second half of the 14th century the church was radically reconstructed. It was then turned into a late Gothic church of the three-nave type. Massive round columns support heavy ribbed vaults cut in stone and an air of peace and sublimity characterizes the church interior in its simplicity. The most valuable part of St. Mark's Church is its south portal, considered being the work of sculptors of the family Parler from Prague (the end of the 14th century). The Gothic composition of the portal consists of fifteen effigies placed in eleven shallow niches. On top are the statues of Joseph and Mary with the infant Jesus, and below them one can see St. Mark and the Lion; the Twelve Apostles are placed on both sides of the portal (four wooden statues replaced the original ones which had been destroyed). In its artistic composition and the number of statues, this portal is the richest and the most valuable Gothic portal in South Eastern Europe. When guilds developed in Gradec in the 15th, and later in the 17th centuries, being the societies of craftsmen, their members including masters, journeymen and apprentices would gather regularly in St. Mark's Church. Outside, on the northwest wall of the church lies the oldest coat of arms of Zagreb with the year 1499 engraved in it (the original is kept in the Zagreb Town Museum).

As the corner of St. Mark's Square and the present day Cirilometodska Street, was a Town Hall, the seat of the city administration in medieval times. The building has gone through a number of alteration and reconstruction phases, and today this old Town Hall still keeps its doors open for the meetings of the Zagreb Town Council. On the opposite side of the Square at the corner of Basaritekova Street lies St. Mark's parish office. The house has been standing there since the 16th century, although it underwent reconstruction in the 18th century and had an extension added in the 19th century. At the west end of St. Mark's Square, the mansion called Dvori, the former residence of the Civil Governor of Croatia, was built at the beginning of the 19th century and yet, it can be classed among the Zagreb antiquities. The government of the Republic of Croatia meets in the Baroque mansion beside it. Since 1734, the Croatian Sabor (parliament) has taken up the east side of St. Mark's Square.

Very little is known today of the outward appearance of medieval Vlaska Street. The name of the settlement was Vlaska Ves, of Vicus Latinorum in Latin. In the old part of the present day VIaska Street, below the archbishop's residence and gardens, lies a row of houses built at the end of the 18th and the beginning of the 19th centuries, and thus the line of their facades shows the course of the old road.

In medieval documents a mention was made of watermills and public baths which existed along the Medvestak Stream in the valley between Gradec and Kaptol. The road construction in that area began in the 18th and the first half of the 19th centuries. The east bank of the stream was under the jurisdiction of Kaptol, and the west bank under Gradec.
St. Mark's Church in the middle of the Upper Town
View of the medieval settlement of Kaptol
View of the Cathedral and Kaptol Square
The hill city of Gradec