According to the results of this study, a road tunnel was recommended as the solution that offered the highest degree of feasibility.

[4][16] The Ministry of Transportation, Maritime and Communication of Turkey commissioned a feasibility study by Nippon Koei Co. Ltd. in 2005 to assess route alternatives for a new tunnel crossing.

Based on environmental and social criteria, cost and risk factors, the study concluded by supporting the initially proposed route as the preferred option.

[citation needed] The three current bridges across the Bosphorus were taken into consideration in selecting the tunnel's location, which was put farther south to better balance the distribution of traffic between the crossings.

Other selection criteria included the route's lower investment cost due to a shorter tunnel length and the availability of sufficient space for construction sites and operational buildings (toll plaza, administrative units).

High level assessments based on corridor alternatives that are comprehensively defined in the feasibility study also support the selection of the proposed route in terms of environmental and social costs and risk factors.

[4][16] The build–operate–transfer model adopted at the Eurasia Tunnel, has brought together the private investment dynamism and their project experience, and the support of international financial institutions.

[4] The project consists of three main segments: Construction of five U-turns as underpasses and seven pedestrian crossings as overpasses along Kennedy Street that stretches between Kazlıçeşme and Sarayburnu as a shoreline road beside the Sea of Marmara.

[4][11] The tunnel alignment is located in a seismically active region, about 17 km (11 mi) to the North Anatolian Fault Zone.

The 3,340 m (3,650 yd) tunnel was excavated and constructed with a 13.7 m (45 ft) diameter Mixshield Slurry TBM exclusively designed and equipped with the latest 19 in (483 mm)} disc cutters (35 pieces monoblock disc cutters, all atmospherically changeable and have individual wearing sensor system), 192 piece cutting knives (only 48 atmospherically changeable), special pressurized locks for divers and material and rescue chamber for all shift members.

Furthermore, 440 disc cutters, 85 scrapers and 475 brushes were replaced by TBM crew and four times hyperbaric maintenance operations (total of 45 days) with specially trained divers (max.

Each ring consists of nine segments that had an average 28 day cylinder compressive strength of 70 MPa (10,000 psi) and can resist at least 127 years as a service life against subsea conditions.

These tunnels were excavated in Trakya Formation from four faces with a 1.4 m/d (4.6 ft/d)/face advance rate under a densely populated district with minimum and maximum overburden of 8 and 41 m (26 and 135 ft), respectively.