BULGARIA COUNTRY GUIDE — reviewed 24 October 2026
Route: /atlas/bulgaria

SCOPE AND METHODS
28 provinces (oblasti), 24 approximate city centres, 16 sight pins, four
selected waters, ten illustrated topics, thirty FAQs and ten existing Bulgarian
lessons. Sofia City (BG-22) and Sofia Province (BG-23) are separate units.
Province labels follow common English spellings. These units are not
municipalities or statistical planning regions.

Water geometry retains complete named Natural Earth source main courses,
without intersection with Bulgaria's border or the opening camera. Danube
includes Donau, from Germany to its Black Sea delta. Maritsa includes the
Evros/Meric reach to the Aegean; Struma includes Strymon to the Aegean.
The Black Sea retains its full marine polygon. Smaller headwater channels
and contemporary shoreline details may be absent from this generalised
1:10m source. Tributaries remain separate from named main courses.
No artificial offshore borders are drawn. The camera can zoom out to the
full courses. These are learning maps, not navigation or hydrological charts.

MAP SOURCES AND REBUILD
Natural Earth 1:10m, public domain:
https://www.naturalearthdata.com/about/terms-of-use/
https://github.com/nvkelso/natural-earth-vector/tree/master/geojson
ne_10m_admin_1_states_provinces.geojson (BGR province features)
ne_10m_rivers_lake_centerlines.geojson (Danube, Donau, Evros, Strymnas)
ne_10m_geography_marine_polys.geojson (Black Sea; retained Romania snapshot)
Downloaded 24 October 2026. Selected source features are retained in
scripts/bulgaria-map-source.geojson. Coordinates and learning text are in
scripts/bulgaria-map-places.json. Rebuild with Python 3 and Shapely 2:
python3 scripts/build-bulgaria-maps.py
City and sight coordinates are curated approximate locations, not entrances,
access advice, walking routes, or statements of current opening hours.

FACTS AND READING REFERENCES
European Union — Bulgaria, institutions and accession:
https://european-union.europa.eu/principles-countries-history/eu-countries/bulgaria_en
European Commission — Bulgaria and the euro (adopted 1 January 2026):
https://economy-finance.ec.europa.eu/euro/eu-countries-and-euro/bulgaria-and-euro_en
European Central Bank — Bulgaria (fixed conversion: EUR 1 = BGN 1.95583):
https://www.ecb.europa.eu/euro/changeover/bulgaria/html/index.en.html
Council of the EU — Schengen internal land controls lifted 1 January 2025:
https://www.consilium.europa.eu/en/press/press-releases/2024/12/12/schengen-council-decides-to-lift-land-border-controls-with-bulgaria-and-romania/
National Assembly — constitutional institutions and 240 ordinary members:
https://www.parliament.bg/en/const
National Statistical Institute — 2021 census (6,519,789 residents):
https://www.nsi.bg/en/content/19641/basic-page/census-2021
NATO — members (Bulgaria joined in 2004):
https://www.nato.int/cps/en/natohq/topics_52044.htm
Bulgarian Ministry of Tourism — cultural and natural destinations:
https://bulgariatravel.org/
United States Holocaust Memorial Museum — Bulgaria:
https://encyclopedia.ushmm.org/content/en/article/bulgaria
The survival of most Jews within prewar borders is distinguished from the
deportation and murder of Jews from Bulgarian-occupied territories.

UNESCO WORLD HERITAGE
Rila Monastery https://whc.unesco.org/en/list/216/
Boyana Church https://whc.unesco.org/en/list/42/
Thracian Tomb of Kazanlak https://whc.unesco.org/en/list/44/
Madara Rider https://whc.unesco.org/en/list/43/
Ancient City of Nessebar https://whc.unesco.org/en/list/217/
Rock-Hewn Churches of Ivanovo https://whc.unesco.org/en/list/45/
Thracian Tomb of Sveshtari https://whc.unesco.org/en/list/359/
Pirin National Park https://whc.unesco.org/en/list/225/
Srebarna Nature Reserve https://whc.unesco.org/en/list/219/
March cultural practices https://ich.unesco.org/en/RL/01287
Nestinarstvo https://ich.unesco.org/en/RL/00191

PHOTOGRAPHS
Hero: Plovdiv Roman theatre, MrPanyGoff, CC BY-SA 3.0.
Existing Bulgarian Speak photographs retain their Commons links and credits
in european-speak-heroes.json and speak-challenge-heroes.json.
Food: Banitsa and yogurt, Biso, CC BY 3.0.
Nature: Rila 7 lakes circus panorama 3, Javier Sanchez Portero, CC BY-SA 3.0.
Politics: National Assembly of Bulgaria, Plamen Agov, public domain.
Economy: Roses pickers in roses vally, kazanlak, bulgaria, Avishai Teicher,
public domain. New photographs are resized; source pages and licence URLs
are retained beside the local files under images/country-guides/bulgaria/.

QUIZ REVIEW
All 80 Bulgarian seed questions are reviewed through prompt-key read-time
patches in bulgaria-facts-patches.json; stored lesson IDs and progress remain.
The review updates euro adoption, Schengen stages, Ottoman conquest,
independence, Cyrillic origins, Holocaust history and ambiguous rankings.
Each question has four distinct options of comparable length. Correct choices
are distributed equally among the four source positions (20 each); runtime
shuffling also applies. No "both B and C" choices remain. The original seed
and database are unchanged. Tests enforce a per-question character spread
of at most six characters or 26 percent of the longest choice, whichever
is larger. This is an editorial aid, not a substitute for factual review.