5 September 2025 The Future is the Product of the Past

A Rare Design in Roman Military Architecture: Triangular Stone Tower Discovered Near Sofia

Bulgarian archaeologists have uncovered a triangular stone tower — a rare architectural form in Roman military design — at the Kokalanski Urvich fortress just outside Sofia. Dated to the late 2nd century AD, the structure sheds new light on Roman-era military planning and the early strategic significance of the Sofia region.

The discovery, described as one of the most unique finds in recent decades, was made by Dr. Filip Petrunov and Violina Kiryakova during the final phase of an excavation funded by Sofia Municipality’s “Culture” programme.

The tower was found 1.7 meters below the surface, embedded in massive stone foundations shaped in a distinct triangular layout — a rare design in Roman military architecture. This configuration immediately caught the attention of experts from the National History Museum, as it suggests a strategically planned defensive structure that predates many known fortifications in the region.

A Hidden Link to Ancient Serdica

What makes this discovery even more extraordinary is its historical alignment with the development of ancient Serdica, the Roman predecessor of modern-day Sofia. Scholars believe the tower was constructed during the same period as Serdica’s urban rise, linking the two sites in a broader narrative of Roman expansion and strategic defense across the Balkans.

The earliest coins recovered from the site — dating back to the reign of Roman Emperor Caracalla (211–217 AD) — further cement the tower’s 2nd-century origins. According to the excavation team, this is the oldest structure ever found at the Urvich site, revealing that the fortress held a strategic role far earlier than previously thought.

Plan of the medieval Bulgarian fortress Urvich. Credit: Wikipedia Commons

Layered History: From Rome to Byzantium

The tower’s historical relevance doesn’t stop with the Romans. Archaeologists also found signs of continued occupation and reconstruction across centuries, pointing to its multi-period importance. Evidence of later structural reinforcements and fortifications, including Byzantine stonework, suggests that the tower remained a key military outpost well into the medieval era.

Of particular note is a Byzantine coin bearing the image of Emperor Isaac II Angelos (1185–1195 AD). This artifact provides direct evidence of 12th-century reconstruction efforts, implying that the fortress was re-integrated into the defensive network of the Second Bulgarian Empire or late Byzantine territories.

This continuity of use over more than a millennium demonstrates not only the architectural durability of the site but also its enduring geostrategic value in the Balkans.

Public Engagement: Making the Past Accessible

Alongside the excavation work, new informational signage has been installed at the Kokalanski Urvich site to help visitors interpret the area’s most significant archaeological features. The initiative is part of the National History Museum’s project “The House of the Double-Headed Eagle”, which aims to socially integrate historic sites into public life and raise awareness of Bulgaria’s cultural heritage.

This project is a vital step toward cultural tourism development, providing an educational experience for locals and international visitors alike. The triangular tower, with its layered Roman and Byzantine past, now stands not only as an archaeological find but as a living monument to Bulgaria’s rich historical continuum.

Triangular Stone Tower Dating from the Late 2nd Century Discovered near Sofia. Credit: BNT
Triangular Stone Tower Dating from the Late 2nd Century Discovered near Sofia. Credit: BNT

Connecting the Dots: The Serdica Triangle and Kokalanski Urvich

The triangular design of the newly uncovered tower has drawn comparisons to the Serdica Triangle in central Sofia, where Roman ruins lie beneath the modern capital’s government buildings. While the Serdica Triangle represents urban civic planning, the Urvich tower appears to be its military counterpart, reinforcing the strategic web that supported Roman Serdica’s rise.

By connecting these two “triangles,” historians are piecing together a broader vision of Roman infrastructure, defense, and governance in ancient Thrace.

A Triangular Key to Bulgaria’s Past

The discovery of the triangular tower at Kokalanski Urvich is more than just an archaeological event — it’s a window into a layered, dynamic history that spans empires and centuries. As excavation efforts continue and public engagement grows, this site may well become a cornerstone of Bulgaria’s historical tourism and academic research landscape.

Cover Image Credit: Kokalanski Urvich fortress near Sofia. Wikipedia Commons

Related Articles

The discovery of a 380-million-year-old heart sheds new light on our bodies’ evolution

16 September 2022

16 September 2022

Researchers from Curtin University have discovered the world’s oldest heart in a ‘beautifully preserved’ ancient jawed fish fossil 380 million...

In Poland’s “Death Valley,” new evidence of Nazi atrocities

18 August 2021

18 August 2021

In October 1939, between 30,000 and 35,000 Polish intellectuals, Polish civilians, Jews and Czechs, and German prisoners from psychiatric institutions...

An unexpected shipwreck was unearthed at the Tallinn construction site

18 April 2022

18 April 2022

During the construction of the office building on Lootsi Street in Tallinn, Estonia’s capital on the Baltic Sea, a shipwreck...

Bronze Age and Roman-era settlements unearthed in Newquay

10 April 2023

10 April 2023

Archaeologists from the Cornwall Archaeological have uncovered ancient dwellings from the Bronze Age and a Roman period settlement in Newquay,...

World’s Largest Geoglyphs Found in the Thar Desert

29 May 2021

29 May 2021

A massive spiral encompassing 100,000 square meters unearthed in the Indian desert may be the greatest drawing ever drawn. The...

Scientists identified a unique engraving that could be the oldest three-dimensional (3D) map in the world

4 January 2025

4 January 2025

Scientists working in the Ségognole 3 cave, located in the famous sandstone massif south of Paris have identified a unique...

Well-Preserved Funerary Enclosures, Mausoleums, and Gladiator Epitaph Discovered in Ancient Roman Colony of Liternum, Italy

22 March 2025

22 March 2025

Recent archaeological excavations in the ancient Roman colony of Liternum, located in present-day Giugliano in Campania, Italy, have unveiled significant...

First example of Roman crucifixion in UK discovered in Cambridgeshire village

8 December 2021

8 December 2021

In Cambridgeshire village, the earliest evidence of a Roman crucifixion has been discovered. Archaeologists investigating a previously unknown Roman roadside...

Ancient Footprints Offer Evidence Humans Wore Shoes 148,000 Years Ago

12 September 2023

12 September 2023

A new analysis of ancient footprints in South Africa suggests that the humans who made these tracks might have been...

Archaeologists Uncover Early Bronze Age Ceremonial Complex in Murayghat, Jordan

4 August 2025

4 August 2025

Archaeologists have uncovered striking evidence of an ancient ceremonial complex in Murayghat, Jordan, that could rewrite what we know about...

11,000-Year-Old LSU Campus Mounds Are Oldest Known Human-Made Structures In North America

23 August 2022

23 August 2022

According to new research published in the American Journal of Science, two six-meter (20-foot) high mounds on the campus of...

Hiker found a place of holy worship at an altitude of 2,590 meters in the Swiss Alps

15 March 2023

15 March 2023

A trekking enthusiast stumbled upon an ancient Roman coin buried in rubble in a remote area high in the Alps...

1,800-Year-Old Sanctuary to Mithras discovered in Spain

8 February 2023

8 February 2023

Archaeologists excavating at Villa del Mitra in Cabra, Spain, have uncovered a sanctuary dedicated to the god Mithras, along with...

An ancient Roman road has been discovered in the Venice Lagoon

24 July 2021

24 July 2021

Researchers discovered a Roman road submerged in the Venice Lagoon. The finding suggests that substantial communities may have existed in...

1800-year-old marble inscription found in Turkey’s Aigai excavations deciphered

2 October 2022

2 October 2022

The 1800-year-old inscription, consisting of 3 pieces of marble, found in the excavations in the ancient city of Aigai in...