Question: In what oblast is the oldest city in the northeast located?

Knowledge 1: Kievan Rus'
In the northeast, Slavs from the Kievan region colonized the territory that later would become the Grand Duchy of Moscow by subjugating and merging with the Finnic tribes already occupying the area. The city of Rostov, the oldest centre of the northeast, was supplanted first by Suzdal and then by the city of Vladimir, which become the capital of Vladimir-Suzdal'. The combined principality of Vladimir-Suzdal asserted itself as a major power in Kievan Rus' in the late 12th century. In 1169 Prince Andrey Bogolyubskiy of Vladimir-Suzdal sacked the city of Kiev and took over the title of the (Великий Князь/Velikiy Knyaz/Grand Prince or Grand Duke) to Vladimir, this way claiming the primacy in Rus'. Prince Andrey then installed his younger brother, who ruled briefly in Kiev while Andrey continued to rule his realm from Suzdal. In 1299, in the wake of the Mongol invasion, the metropolitan moved from Kiev to the city of Vladimir and Vladimir-Suzdal. [SEP] Knowledge 2: Rostov
Rostov () is a town in Yaroslavl Oblast, Russia, one of the oldest in the country and a tourist center of the Golden Ring. It is located on the shores of Lake Nero, northeast of Moscow. Population:
Knowledge 1: Kievan Rus'
In the northeast, Slavs from the Kievan region colonized the territory that later would become the Grand Duchy of Moscow by subjugating and merging with the Finnic tribes already occupying the area. The city of Rostov, the oldest centre of the northeast, was supplanted first by Suzdal and then by the city of Vladimir, which become the capital of Vladimir-Suzdal'. The combined principality of Vladimir-Suzdal asserted itself as a major power in Kievan Rus' in the late 12th century. In 1169 Prince Andrey Bogolyubskiy of Vladimir-Suzdal sacked the city of Kiev and took over the title of the (Великий Князь/Velikiy Knyaz/Grand Prince or Grand Duke) to Vladimir, this way claiming the primacy in Rus'. Prince Andrey then installed his younger brother, who ruled briefly in Kiev while Andrey continued to rule his realm from Suzdal. In 1299, in the wake of the Mongol invasion, the metropolitan moved from Kiev to the city of Vladimir and Vladimir-Suzdal. [SEP] Knowledge 2: Sokolniki District
Sokolniki District () is a district of the Eastern Administrative Okrug of the federal city of Moscow located in the north-east corner of the city. Population:
Knowledge 1: Kievan Rus'
In the northeast, Slavs from the Kievan region colonized the territory that later would become the Grand Duchy of Moscow by subjugating and merging with the Finnic tribes already occupying the area. The city of Rostov, the oldest centre of the northeast, was supplanted first by Suzdal and then by the city of Vladimir, which become the capital of Vladimir-Suzdal'. The combined principality of Vladimir-Suzdal asserted itself as a major power in Kievan Rus' in the late 12th century. In 1169 Prince Andrey Bogolyubskiy of Vladimir-Suzdal sacked the city of Kiev and took over the title of the (Великий Князь/Velikiy Knyaz/Grand Prince or Grand Duke) to Vladimir, this way claiming the primacy in Rus'. Prince Andrey then installed his younger brother, who ruled briefly in Kiev while Andrey continued to rule his realm from Suzdal. In 1299, in the wake of the Mongol invasion, the metropolitan moved from Kiev to the city of Vladimir and Vladimir-Suzdal. [SEP] Knowledge 2: Paris
Paris is located in northern central France. By road it is 450 kilometres (280 mi) south-east of London, 287 kilometres (178 mi) south of Calais, 305 kilometres (190 mi) south-west of Brussels, 774 kilometres (481 mi) north of Marseille, 385 kilometres (239 mi) north-east of Nantes, and 135 kilometres (84 mi) south-east of Rouen. Paris is located in the north-bending arc of the river Seine and includes two islands, the Île Saint-Louis and the larger Île de la Cité, which form the oldest part of the city. The river's mouth on the English Channel (La Manche) is about 233 mi (375 km) downstream of the city, established around 7600 BC. The city is spread widely on both banks of the river. Overall, the city is relatively flat, and the lowest point is 35 m (115 ft) above sea level. Paris has several prominent hills, the highest of which is Montmartre at 130 m (427 ft). Montmartre gained its name from the martyrdom of Saint Denis, first bishop of Paris, atop the Mons Martyrum, "Martyr's mound", in 250.

Answer: Yaroslavl Oblast