Driving down the ancient Via Flavia road from Buje to Vizinada, you will notice a 228-metre high cone-shaped hill on the left. At the top of the hill, among the houses, you can see a church tower. This is Groznjan, the ancient Graeciniana. The terraced hill, covered with old vineyards and olive gardens, is actually a sandy elevation created from the erosion of two streams, the Kanistran and the Pision. The town's poetic coat of arms shows an arm holding a white lily and reaching towards the sun. Povijesni tekstovi prvi puta spominju GROŽNJAN 1102. godine. From Groznjan you can enjoy a view of about 20 surrounding villages, fields on the Bolara and Kostanjica hillsides on the left, meadows of the Bijele zemlje (White Lands) and Baredina slopes on the right, the Mirna valley below, and the coastline from Novigrad to Umag. This is one of the most beautiful and most fertile areas in Istria.
The land around Groznjan is partly mountainous and partly flat, very fertile, with many olive groves, vineyards and orchards. By the town gate there is St. Nicholas cemetery with many cypress trees, and about a kilometer to the northwest there is a gentle plateau of St. Vitus with and old, abandoned cemetery and a little church with mortuary. At the edges of the plateau there are Peroj and Rimska palaca (Roman Palace), where mosaic pieces, Roman coins, and remains of a rich settlement and a road have been found. The Groznjan area also includes St. Florian on the Karst, and it ends with the Mirna river in the south, where the Bastija harbour used to be. In 1500 boats still sailed up the Mirna to this harbour. In the west the Groznjan territory once included Nova Vas, a little town near Brtonigla. In 1371 the Nova Vas area, including the St. George castle on the Mirna, came under the rule of Venetian podesta situated in Groznjan.
The town, once known as kastel (castle), was surrounded by thick walls, the remains of which are now a valuable historic heritage. It had two gates, and the one still existing, called the Great Gate, used to have a drawbridge. It is situated in a beautiful place where a road from Ponte Porton ends. From a magnificent lookout on the wall, where once the smaller gate used to be and where a Venetian column still stands, one can see far to the horizon. The houses are built tightly next to each other, in the typical medieval style. In the church of Sts. Vitus, Modest and Crescentia there is an altar, believed to have special powers, which was donated by pope Pius VII in 1800. It was handed through special edict to the priest Michele Dubaz during the pope's visit to Tarska vala (Tar Cove), where his frigate Bellona took refuge from a storm.
Between the two town gates, on a little square outside the walls, there is a small church built in 1554, as inscribed in a stone above the entrance. It was dedicated to Sts. Cosimo and Damian, and renovated in 1834. The spire has been preserved, but there is no church bell. The interior and a large atrium supported by fragile columns were renovated in 1954, and in 1986 a renowned Croatian artist Ivan Lovrencic painted the interior. Apsidal cathedral in the centre of Groznjan was built in the 14th century and renovated in the baroque style in 1770, when four supporting beams and capitals on the façade were added. The cathedral, originally dedicated to Virgin Mary, is today a church of Sts. Vitus, Modest and Crescentia. The parish church was first mentioned in 1310. Its interior was repainted in 1965. Pews, decorated in folk tradition, were built during the Renaissance. The sacristy and a reliquary date from 1612. A large painting in the bottom of the church, known as the painting of the patron saint, was done by Ermengildo de Troy and depicts the martyrdom of saints Vitus, Modest and Crescentia in the Roman Colosseum in 303. Next to the church is a tall bell tower, octagonal at the top and built of yellow sandstone. Near the parish church there used to be two small churches, of St. Rocco and St. Martin, built in the 14th century. A Venetian loggia fontica from 1557 has, fortunately, remained. It has four columns and a limestone floor; inside there are four Roman tombstones. This ancient loggia used to be a court's meeting place.
Groznjan once had its own statute consisting of four books and written in Italian in 1558. It seems, though that the town had its own statute as early as 1358, the year it became a part of the Venetian Republic. Code of law and the statute are written on the parchment paper, and include a miniature of Madonna flanked by St. Vitus and St. Modest, with the town's coat of arms below them. Legend has it that on the first day of Lent judges made fritulas and gave them to passers-by, who were supposed to pay their respects or otherwise they would be fined. Podesta's palace in Groznjan was renovated twice, in 1588 and 1726. During the centuries Groznjan and surrounding area were inhabited by various peoples and changed many rulers. Histrians, Illyrians, Celts, Greeks, Romans, Ostrogoths, Langobards, Franks, Germans, Slavs, Italians and others have lived, mixed and fought for power there. Groznjan was once a Roman fort and various inscriptions, coins, mosaics, as well as toponyms like Vrh Roman (Roman Peak), speak of their presence.
The fort of Groznjan was first mentioned in 1102, when Istrian marquis Ulrich II and his wife Adelaide donated their Istrian property to a patriarch of Aquileia. In this document the burg was called Castrum Grisiniana. In 1238 it was probably ruled by Vicard I Pietrapelosa. In 1277 a number of Slavic families were invited to settle and cultivate the fiefdom's lands. In 1286 Vicard II Pietrapelosa pledged the fort with patriarch Raymond as a guarantee of war reparations. In 1287 Vicard aligned with Venetians, his former enemies, and gave Groznjan to them. After the war the fort was returned to its previous owners. Vicard's son Pietro inherited Groznjan after his father's death in 1329, and when he died in 1339 it again became patriarch's property. The patriarch rented it to Furlanian noble family de Castello. In 1354 Groznjan's new owner became Volrich, or Ulrich, Reifenberg, who in 1358 sold it to Venice for 4,000 ducats in order to pay his debts. Volrich was a son of Deitalm, a descendant of Aquileian patriarch Volcher, and in 1356, during the war between Venice and Hungary, his army, entrenched in Groznjan, strongly resisted the Hungarian army. Yet it seems that at the same time Volrich negotiated the surrendering of Groznjan in Venice. The town was probably taken by Hungarian and Croatian troops led by Mikiza, a son of the Croatian vice-roy.
Archdeacon of Budim, who documented it, called the town Krisignan of Volrich Rosumberk. Venice took Groznjan over in 1358 and ruled until its demise in 1797. Slavic families, invited by German feudal lords, settled in the abandoned villages of the area as early as the 14th century, before Venice bought Groznjan. In 1359 the Umag captain Pietro Dolfin moved to his new residence in Groznjan, and in 1360 and 1367 he fortified the town walls and renovated the palace. Captain's Office moved from Groznjan to Raspor in 1394, when a central rule, which included Sveti Lovrec Pazenaticki, was established for the whole area. Since then Groznjan was governed by Venetian noblemen who were given the title of podesta.
From the early 16th century Groznjan's podestas were chosen among Koper noblemen. In the 15th century judicial duties were performed by the Pietrapelosas, and in 1446 the town walls were fortified in order to protect from possible Turkish attacks. After the terrible plague in 1630 the Groznjan area became almost completely deserted. In order to revitalize the area the St. Mark's Republic brought Italian families from Veneto, Carnia and Furlania provinces; these were mostly tradesmen who settled in towns. Slavic families were settled in villages in order to develop agriculture. All settlers in Istria were given free land and were exempt from fiscal duties and work obligations for twenty years; the only condition was to cultivate the land within five years. Economic success of colonization of villages reflected on the towns as well: trade and transportation developed and demographics improved. After the fall of Napoleon's Empire in 1813, his Illyrian provinces, including Groznjan, became part of the Habsburg Empire. In 1816 Austrian emperor Francis I visited Groznjan on his tour through Istria and met with the local clergy and population.