The Ob River (Russian: Обь; IPA: [opʲ]), also Obi, is a major river in western Siberia, Russia and is the world's seventh longest river. It forms at the confluence of the Biya and Katun rivers which their origins in the Altay Mountains. It is the westernmost of the three great Siberian rivers that flow into the Arctic Ocean (the other two being the Yenisei River and the Lena River). The Gulf of Ob is the world's longest estuary.
The Ob is known to the Khanty people as the As, Yag, Kolta and Yema; to the Nenets people as the Kolta or Kuay; and to the Siberian Tatars as the Umar or Omass. Possibly from Proto-Indo-Iranian *ap-, "river, water" (compare Persian āb, Tajik ob, and Pashto obə, "water").
The Ob forms 25 km (16 mi) southwest of Biysk in Altai Krai at the confluence of the Biya and Katun rivers. Both these streams have their origin in the Altay Mountains, the Biya issuing from Lake Teletskoye, the Katun, 700 kilometres (430 mi) long, bursting out of a glacier on Mount Byelukha.
OB or Ob may refer to:
Oba-Igbomina (in Yoruba correctly Ọ̀bà, but also written as Òbà), is an ancient Igbomina town in northeastern Isin Local Government Area of Kwara State. It is one of the five related Yoruba towns named "Oba", the others being
The original Ọ̀bà was the capital of an ancient Ọ̀bà civilization, a kingdom reputed in the oral history of the region as a center of great wealth and enterprise. Most of the extant Oba towns claim to be the original Oba or claim to be the oldest derivative of the ancient civilization.
Recent archaeological research results and published works of oral history experts, anthropologists and archeologists of the Arizona State University, USA and the University of Ibadan, Nigeria, of the region's contemporary and later settlements suggest that Ọ̀bà was founded between the 9th and 10th centuries. Regular conflicts with the neighbouring Nupe resulted in cycles of abandonment and reoccupation of the Òbà mother city.