The International Terrestrial Reference Frame defines and maintains the global reference coordinate system. It is based on the observations from space geodesy techniques at geodetic stations. Beside collocated stations with more than one space geodesy technique the geodetic stations at stable regions without local movements must be used. So, during maintenance of geodetic stations must be secured that the stations are not subject to local movements. The case study is presented for the station at the Geodetic Observatory Pecny, Czech Republic. The vertical movements are monitored by repeated levelling technique. The systematic errors in the length of the levelling rod and the correction due to an inclined line of sight were accounted during processing. The results of the measurements from 2001 to 2017 are summarized. No local motion of the GNSS station or of the absolute gravity point has been demonstrated. The results are compared and discussed with the coordinate time series determined by GNSS and the gravity acceleration time series from the relative superconducting gravimeter calibrated by the absolute gravimeter.