Third Mainland Bridge is the longest of three bridges connecting Lagos Island to the mainland, the others are the Eko and Carter bridges. ^ "Longest Bridge in Africa Strengthened using GEWI® Bars". Archived from the original on 2013-06-22. Wikimedia Commons has media related to List of bridges in Nigeria. The bridge is a 2 × 4 lane carriageway cross-sectional road with permission for. Nigeria is a land filled with many infrastructural designs.