Context : Whether the Cygnus X complex consists of one physically connected region of star formation or of multiple independent regions projected close together on the sky has been debated for decades .
The main reason for this puzzling scenario is the lack of trustworthy distance measurements .

Aims : We aim to understand the structure and dynamics of the star-forming regions toward Cygnus X by accurate distance and proper motion measurements .

Methods : To measure trigonometric parallaxes , we observed 6.7 GHz methanol and 22 GHz water masers with the European VLBI Network and the Very Long Baseline Array .

Results : We measured the trigonometric parallaxes and proper motions of five massive star-forming regions toward the Cygnus X complex and report the following distances within a 10 % accuracy : 1.30 ^ { +0.07 } _ { -0.07 } kpc for W 75N , 1.46 ^ { +0.09 } _ { -0.08 } kpc for DR 20 , 1.50 ^ { +0.08 } _ { -0.07 } kpc for DR 21 , 1.36 ^ { +0.12 } _ { -0.11 } kpc for IRAS 20290+4052 , and 3.33 ^ { +0.11 } _ { -0.11 } kpc for AFGL 2591 .
While the distances of W 75N , DR 20 , DR 21 , and IRAS 20290+4052 are consistent with a single distance of 1.40 \pm 0.08 kpc for the Cygnus X complex , AFGL 2591 is located at a much greater distance than previously assumed .
The space velocities of the four star-forming regions in the Cygnus X complex do not suggest an expanding Strömgren sphere .

Conclusions :