The Istanbul Metropolitan Municipality (IBB) Council approved Friday plans to build two new tunnel projects on the European side of the city.

The first approved project is a two-way underwater tunnel which will connect Unkapanı and Kasımpaşa districts under the Golden Horn.

Once the tunnel is constructed, the historical Atatürk Bridge, also known as the Unkapanı Bridge, will be disassembled.

The tunnel is expected to be finished in 2018, and will be approximately one-kilometer-long and is expected to cost $34 million.

The tunnel project aims to replace the aging bridge to make up more space in one of Istanbul's most scenic areas.

The second approved project covers three interconnected highway tunnels: A two-kilometer-long tunnel between Dolmabahçe and Fulya districts, a four-kilometer one between Fulya and Levazım districts and a six-kilometer one between Levazım and Baltalimanı districts.

Expected to ease the clogged traffic flow running on north-south axis on the west side of Bosporus by 2018, the tunnels will have a total length of 12 kilometers and will cost $660 million.