This chapter explains first the effect of earthquakes on tunnels excavated with conventional and mechanized tunneling methods, given examples of Bolu and Nurdağı tunnels. Seismic joints designed for both different tunneling methods are also summarized. East Anatolian and North Anatolian faults create tremendous tectonic stresses along the slipping line before the occurrence of the Earthquake. These tectonic stresses affect the performance of TBMs by squeezing the machine as did in the Doğançay tunnel, which is one of the subjects of this chapter. An amount of 7.8 km of Kargı hydropower tunnel is opened with a double shield TBM using precast segments, and 4 km is opened with drilling and blasting method without lining, using only rock bolts. After one year of the operation of the powerhouse, significant collapses were observed in the unlined section of the tunnel. The method of investigation and remedial work of the collapsed area are also given in this chapter. This chapter also details using strand jacks to ease the steering of a 13.7 m diameter double shield TBM in the T26 high-speed tunnel and also the high performance of the 13.8 m diameter XRD TBM in the Eşme-Salihli tunnel.