Vibration monitoring has become important in railway tracks for many purposes. One of the most important purposes is to prevent exceeding limits of induced vibration to adjacent residential buildings. In the current study, to measure the level of vibration, a field investigation is carried at three critical positions including a curve, a fishplate and a deflected rail weld. The field study is an old ballasted railway track located at the critical /one of the entrance of Mashhad Railway station in Iran. In this regard, three distinct field tests are performed using accelerometer sensors and the obtained data arc analyzed and assessed. Besides this, vibrations at 5 and 10 m-distancc from the track arc also considered and rccordcd. As the main achievement, results show that induced vibration levels arc highly dependent on the condition of contact surface between wheel and rail