The Niger Bridge that connects Asaba and Onitsha was commissioned in 1965. See how people travelled then versus now.
The signature 1400m long bridge that links the rest of the country to the South Eastern part is the Niger Bridge, popularly known as the Onitsha bridge. It was constructed between 1964 and 1965, and commissioned by the then Prime Minister late Alhaji Tafawa Balewa and opened for traffic in December 1965. This commissioning of the bridge was the last public function of the Prime Minister before his assassination.
Onitsha in Anambra state has one of the biggest markets in the country and goods and people have to be transported. People travelled smoothly by road until they reach Asaba, Delta, which was separated from Onitsha by the might river Niger. Hence, The Niger Bridge is considered to be of Nigeria’s most economically crucial bridges.

After construction in 1965, the bridge was 8×420 ft. with a carriageway of 36 feet centre-truss and a pedestrian walkway on both sides of the carriageway. However, during the Nigerian civil war (1967 - 1970), retreating Biafran soldiers destroyed the Niger Bridge in order to halt and trap Nigerian military at the other side of the river.
So, how were people travelling before the construction of the bridge?
People from the South-South and South-West had to commute via private ferries of different sizes to the South East and vice versa.

https://www.nigerialog.com/metro/onitsha-bridge-how-people-travelled-then-versus-now/new/#new