Selka is the newest and largest of the five Rapani states in the triangle of lands known as the . The Elirapa is roughly bounded by the Styritsa Mountains to the west, the Dunafolda River to the north and the Vari River to the east. Selka occupies the lands south of the Brissa River and along the Great Road. Selka is the dominant member of the Rapani confederation known as the Northern Marches.
Selka encompasses 289,200 km². It is predominately lowland with hills in the southern and western parts of the March. The Doberai Hills in the western part of Selka occupy about 14% of its total land area. This region is more rugged than the rest of the hill country and is sparsely settled.
2,874,000 Rapani live in Selka, which is almost half of the population of the . The overwhelming majority of them live in the countryside as farmers or ranchers. There are a scattering of market towns in the countryside as well as the administrative capital of Selka (named Selka Town) and the commercial town of Inigol.
There are two main road systems in the Northern Marches. The Great Road runs east to west, from Korslik to Selka Town, connecting Korslik to the United Councilate States. The Pundri Trade Route runs north from Selka Town to Inigol, then across the Brissa River to Koskivere on the north bank of the Dunafolda.
The economic and social life of the countryside is dominated by military organizations known as . Men must either belong to a Rhyde or seek their fortune in a free town.
There are 42 free towns in Selka, in addition to Selka Town and the chartered City of Inigol. The towns operate independently of the structure. Town citizens are exempt from military service. Instead, each town maintains a town militia that performs policing and garrison responsibilities in peacetime and joins the regular army in wartime.
Selka shoulders most of the burden of defending the Vari River border. Every three months, one Selka garrisons the river watchtowers with a mixed force of 120 warriors per tower. A second Rhyde garrisons Fort Inogau, at the mouth of the Brissa River. The Fifth Rhyde patrols the Banakur Forest fringe, sending small patrols deep into the forest and occasionally beyond to raid settlements on the Forest’s eastern fringe.