Editing Geography of Bulgaria (section)

== Boundaries and territory ==
The borders of Bulgaria have a total length of 2,245&nbsp;km; of them 1,181&nbsp;km are land boundary and 686&nbsp;km are formed by rivers. The coastline is 378&nbsp;km.<ref name="donchev16">{{harvnb|Donchev|Karakashev|2004|p=16}}</ref><ref name="borders">{{cite web |url=http://geografia.kabinata.com/01.htm|title=Geographic Position and Borders of Bulgaria|website=Topics of Geography of Bulgaria|access-date=5 August 2015}}</ref>

The northern border with [[Romania]] is 609&nbsp;km. Most of the frontier (470&nbsp;km) is formed by the river Danube from the mouth of the river [[Timok]] in the west to the city of [[Silistra]] in the east. The land border from Silistra to Cape Sivriburun at the [[Black Sea]] is 139&nbsp;km long.<ref name="donchev16"/> The Danube, with steep bluffs on the Bulgarian side and a wide area of swamps and marshes on the Romanian side, is crossed by two bridges&nbsp;– [[New Europe Bridge]] between [[Vidin]] and [[Calafat]], and [[Danube Bridge]] between [[Ruse, Bulgaria|Ruse]] and [[Giurgiu]]. There are 48 Bulgarian and 32 Romanian islands along the river Danube; the largest one, [[Belene]] (41&nbsp;km<sup>2</sup>), belongs to Bulgaria.<ref name="donchev18">{{harvnb|Donchev|Karakashev|2004|p=18}}</ref> The land frontier has three border crossings at Silistra, [[Kardam, Dobrich Province|Kardam]] and [[Durankulak]] at the Black Sea. It is also crossed by a major gas pipeline transporting natural gas from Russia to Bulgaria.<ref name="donchev18"/> 
[[File:Kadiitsa IMG 9979.jpg|thumb|right|250px|alt=a river|A winter view of the [[Vlahina]] Mountain near the border with North Macedonia]]
The eastern border (378&nbsp;km) is maritime and encompasses the [[Bulgarian Black Sea Coast]] from Cape Sivriburun in the north to the mouth of the [[Rezovo River]] in the south.<ref name="donchev18"/> Bulgaria's littoral forms 1/10 of the total Black Sea coastline, and includes two important gulfs, the [[Gulf of Varna]] and the [[Gulf of Burgas]], harbouring the country's two major ports.<ref name="donchev18"/>

The southern border is 752&nbsp;km long, of them 259&nbsp;km are with [[Turkey]] and 493&nbsp;km are with [[Greece]].<ref name="borders"/><ref name="donchev19">{{harvnb|Donchev|Karakashev|2004|p=19}}</ref> The Bulgaria–Turkey frontier runs from the mouth of the Rezovo River in the east through the [[Strandzha]] Mountains and the [[Dervent Heights]], crosses the river [[Tundzha]] at the village of [[Matochina]] and ends at the river [[Maritsa]] at the village of [[Kapitan Andreevo]]. There are three border crossings at [[Malko Tarnovo]], [[Lesovo]] and Kapitan Andreevo.<ref name="donchev19"/> The border with Greece runs from Kapitan Andreevo through several ridges of the [[Rhodope Mountains]], generally following the watershed of the rivers [[Arda (Maritsa)|Arda]] and [[Vacha (river)|Vacha]] on the Bulgarian side, runs through the [[Slavyanka (mountain)|Slavyanka Mountain]], crosses the river [[Struma (river)|Struma]] at the village of [[Kulata]] and runs through the crest of the [[Belasica|Belasitsa Mountain]] to the [[Tumba Peak (Belasica)|Tumba Peak]].<ref name="donchev19"/> There are six border checkpoints at [[Svilengrad]], [[Ivaylovgrad]], [[Makaza]], [[Zlatograd]], [[Ilinden, Blagoevgrad Province|Ilinden]] and Kulata.<ref name="donchev19"/>

The western border is 506&nbsp;km long, of them 165&nbsp;km are with [[North Macedonia]] and 341&nbsp;km are with [[Serbia]].<ref name="borders"/><ref name="donchev20">{{harvnb|Donchev|Karakashev|2004|p=20}}</ref> The frontier with North Macedonia runs from the Tumba Peak in the south through the mountains of [[Ograzhden (mountain)|Ograzhden]], [[Maleshevo Mountain|Maleshevo]], [[Vlahina]] and [[Osogovo]] up to mount Kitka. There are three border crossings near the town of [[Petrich]] and at the villages of [[Logodazh]] and [[Gyueshevo]].<ref name="donchev20"/> The border with Serbia runs from Kitka through the mountainous region [[Kraishte]], including the [[Ruy Mountain]], crosses the valley of the river [[Nishava]], runs through the main watershed of the western [[Balkan Mountains]] and follows the river [[Timok]] for 15&nbsp;km until its confluence with the Danube.<ref name="donchev20"/> There are five border checkpoints at [[Dolno Uyno]], [[Strezimirovtsi]], [[Kalotina]], [[Vrashka Chuka]] and [[Bregovo]].<ref name="donchev20"/>