Cross

The Cross River (Oyono) is the main river in southeastern Nigeria, and the state of Cross River is named for it. It is named after the Manyu River in Cameroon, where it originates. Despite being short by African standards, its catchment receives a lot of rain and spreads out quite a bit. It flows through swampy rainforest with numerous creeks for the final 80 kilometers (50 miles) to the sea, forming an inland delta near its confluence with the Calabar River, about 20 kilometers (12 miles) wide and 50 kilometers (31 miles) long between Oron on the west bank and Calabar on the east bank, more than 30 kilometers (19 miles) from the open sea. The delta empties into a large estuary with a few smaller rivers. The estuary is 24 kilometers (15 miles) wide at its mouth in the Atlantic Ocean. The estuary's eastern bank is in Cameroon, a neighboring country.

The river Aloma, which originates in Benue State and flows into the Cross River in Cross River State, is a major tributary of the Cross River. A large roadway connects Cross River State to its sister state, Akwa Ibom. By boat, the distance between Oron and Calabar is 21 kilometers (13 miles), and by road, it is around 200 kilometers (120 miles). The people of the lower Cross River have traditionally relied on water transportation, and Calabar has long had a large seaport on the Calabar River, about 10 kilometers (6 miles) from the Cross River's confluence and about 55 kilometers (34 miles) from the sea. When it was constructed in 1975, the Itu bridge on the Cross River, which runs along the Itu-Calabar route, was hailed as one of the Gowon administration's crowning achievements.

The Cross River divides two tropical wet forest ecoregions: the Cross-Niger transition woods west of the river between the Cross and Niger Rivers, and the Cross-Sanaga-Bioko coastal forests east of the river between the Cross and Cameroon's Sanaga River. The average annual rainfall in the state ranges from 1,760 mm in the north to 3,100 mm in the south. Cross River is both the name of a national park and a language family.

Length: 304 miles