Three dimensional structure of the Aquila Rift of magnetized neutral gas is investigated by analyzing HI and CO line data .
The projected distance on the Galactic plane of the HI arch of the Rift is r _ { \perp } \sim 250 pc from the Sun .
The HI arch emerges at l \sim 30 ^ { \circ } , reaches to altitudes as high as \sim 500 pc above the plane at l \sim 350 ^ { \circ } , and returns to the disk at l \sim 270 ^ { \circ } .
The extent of arch at positive latitudes is \sim 1 kpc and radius is \sim 100 pc .
The eastern root is associated with the giant molecular cloud complex , which is the main body of the optically defined Aquila Rift .
The HI and molecular masses of the Rift are estimated to be M _ { HI } \sim 1.4 \times 10 ^ { 5 } M _ { \odot \hskip { -5.2 pt } \bullet } and M _ { H _ { 2 } } \sim 3 \times 10 ^ { 5 } M _ { \odot \hskip { -5.2 pt } \bullet } .
Gravitational energies to lift the gases to their heights are E _ { grav:HI } \sim 1.4 \times 10 ^ { 51 } and E _ { grav:H _ { 2 } } \sim 0.3 \times 10 ^ { 51 } erg , respectively .
Magnetic field is aligned along the HI arch of the Rift , and the strength is measured to be B \sim 10 \mu { G } using Faraday rotation measures of extragalactic radio sources .
The magnetic energy is estimated to be E _ { mag } \sim 1.2 \times 10 ^ { 51 } erg .
A possible mechanism of formation of the Aquila Rift is proposed in terms of interstellar magnetic inflation by a sinusoidal Parker instability of wavelength of \sim 2.5 kpc and amplitude \sim 500 pc .