Every capital city has a stream flowing through it. Some have mighty rivers bisecting their centers and others have brooks that are barely visible but whose presence also had an impact on the development of cities. The Bulgarian capital of Sofia has two such streams, Vladaya River to the north of the city center, and the Perlovska to its south.

Its course within the city appears as a concrete channel in a constructed, tree-lined ravine. In spring, the snowmelt from the mountains results in more water in this channel, but for most of the year, it is all but invisible to passersby.
Where it Flows

On this map from 1927 we see the Perlovska flowing through a grid of streets to the south of the city center. Among the countries of Europe, Bulgaria is relatively young, having secured partial independence in 1878 and full sovereignty in 1906. Inspired by western capital cities, Sofia’s ancient hodgepodge of streets were straightened into a grid and the waterways were also forced to conform to it.

From the history site Lost Bulgaria, a rare image of the Perlovska that predated the city’s transformation shows a pointed arch bridge on the outskirts of Sofia. During the long Ottoman rule, Sofia was a city of mahallas- neighborhoods defined by ethnic groups such as the Jews, Greeks, Gypsies, and the native Bulgarians. The design of this bridge is similar to the famous Old Bridge in Mostar, Bosnia that is a UNESCO World Heritage site.

On this map from the year of Bulgaria’s independence, we see the walled city with its maze of streets and neighborhoods. Bulgaria secured its freedom with Russian support, and its flag resembled that of Russia. Culturally the two nations share the Cyrillic alphabet and the predominance of the Orthodox Christian faith. Initially the Russians administered the country from Plovdiv and the Bulgarian leadership was based in the medieval capital of Tarnovo, but within a year the seat of government moved to Sofia, which is neither a seaport nor in the center. Perhaps its interior location made it safer for governing at a time when the Ottomans sought to recapture its lost holdings.

This map from 1912 shows the dramatic transformation of Sofia’s streetscape into its present-day grid. As a New Yorker, I can relate to it as the five boroughs experienced their own grid impositions that erased most of their ancient roads. The transformation of Sofia was more systematic than New York, where there are still plenty of pre-grid roads such as Broadway and Rockaway Boulevard that run diagonally through the rectangular blocks. In contrast to Greenwich Village and the Financial District, there is no Old City in Sofia where one can find tight alleys and narrow streets. The only exceptions to this grid are Stefan Stambolov Boulevard, and the few historical buildings that stand askew to the streets.
Between 1908 and World War Two, Bulgaria was a kingdom ruled by tsars who commissioned architects from Europe’s big empires to modernize the city. With much of its watershed being covered by urbanization, the volume of water in the stream decreased, so it never had the look of a canal that one would see on a similar streetscape in Paris or Amsterdam.

On the Perlovska River, the best example of design from the kingdom period is Orlov Most (Eagles Bridge) that carries Tsar Liberator Boulevard across the stream. Its name honors Russian tsar Alexander II who provided military assistance for Bulgaria’s independence effort. As the city grew, this bridge was widened and the eagles atop columns no longer stand over the creek. On the north side of the city center is the Lions Bridge, both built in 1891 by the same Czech designers, Václav Prošek, his brother Jozef and his cousins Bohdan and Jiří.

During World War Two, Bulgaria allied itself with Nazi Germany and fascist Italy in an effort to regain territories that it lost in the previous world war. It was a controversial decision as most Bulgarians did not want to fight against Russia or persecute their Jewish citizens. Among local communists a partisan movement arose to overthrow the monarchy and install a pro-Soviet regime. Next to the bridge that carries Dragan Tsankov Boulevard across the creek are monuments to the partisans. Following the peaceful end of communist rule in 1990, it was an easy decision to remove statues of Lenin from public squares, but as the partisans were Bulgarian, for now their monument remains on site.

A view of the stream as it appears naturally can be seen to the east of the city, where it descends from the Kamen Del peak, collects tributaries and enters the city.

Among the named tributaries is Boyanska Reka, which flows in the median of Alexander Suvorov Street, under Tsar Boris III Boulevard, and in the median of Kyustendil Street, then underneath Bulgaria Boulevard, where it merges with the Perlovska River. Every name on the map has historical significance, honoring Russian commanders, Bulgarian leaders, and places.
Lovers Bridge


Near the underground confluence of the Boyanska and Perlovska streams is an outpost of American fast food, atop the stream, on the median of Bulgaria Boulevard. Running above this McDonald’s restaurant, the boulevard, and the stream, is Lovers Bridge, which connects the Earth and Man National Museum to the Palace of Culture, both of which stand in large parks. In this regard, the footbridge serves as Sofia’s version of the High Line. Throughout the year it is decorated with posters and sculptures, with plants on its sides for a naturalistic look. The origin of its name is a mystery, likely resulting from its status as a popular walk for couples. Upon crossing Fritjof Nansen Boulevard, the creek reemerges on the surface, in the median of the boulevard.


At Shipka Street and at Madrid Boulevard, the stream is enveloped by trees, serving as a linear park. At the time when the channel was constructed, there was plenty of open space here and now the last significant patch of greenery is the boulevard median. Along its route, this linear park borders on South Park, Borisova Gradina Park, Military Academy Park, and Zaimov Park. In this regard, it is reminiscent of Pelham and Mosholu parkways in the Bronx, which connect the Van Cortlandt, Bronx, and Pelham Bay parks.


East of the city center, the architecture becomes less dense and more modernist, with apartment towers from the communist period and office buildings from this millennium.

At Rezbarska Street the concrete channel ends and the Perlovska, whose name translates as Pearl River, flows again on a natural course. It later receives its tributary, the Slatinska Reka, which has a similar story of concrete channels and tunnels within the city. The Perlovska flows into the Iskar River near the wastewater treatment plant that is far outside the city. It is the longest river that flows entirely within Bulgaria. At the village of Gigen, it joins the Danube River, which flows to the Black Sea.

As cities develop, it is tempting for authorities to cover up small streams in favor of parking and roads. The water is deprived of sunlight and oxygen. On Milen Tsvetkov Boulevard is an example of an unused space that covers the stream. It could easily be removed to provide daylight to it. Alternatively, it can also serve as a public square with seating and monuments.


In 2012 there was a proposal by local architects to redesign the channel, giving it a more parklike appearance, inspired by the Cheonggyecheon Stream in Seoul. Another proposal in 2020 imagines the channel’s walls used as an outdoor art gallery. A year later, there was a proposal to have bike ramps descend to the channel, so that it can serve as a bike path when the water level is low. Bulgaria is a member of NATO and the European Union, solidly democratic. Inspired by its western partners, I can imagine some of these proposals becoming a reality, enhancing the appearance of this hidden urban waterway.
Learn More:
For other examples of hidden urban waterways in this corner of Europe, see my earlier essays on Dâmbovița River in Bucharest, Canalul Morii in Cluj-Napoca, and the Szinva River in Miskolc. I welcome requests from readers on documenting hidden urban waterways with interesting histories and sights. Do so with a comment below.
In the News:
WDET reports on proposals to daylight hidden waterways in Detroit.
Gothamist reports on the opposition of environmental groups to storm surge barriers around New York City.