Syllerran Rift

The Syllerran Rift was a spatial anomaly, a pink-colored nebula-like region extending over several light-years in the galaxy's DeltaQuadrant. 

Size and location
The rift lay circa 70.000 light-years from Sol. The Syllerran Rift overlaid a stretch of the coreward-facing border of the vast Nekrit Expanse, but more rimward than the Parein system. The rift was longer than it was deep, with a depth below 20 lightyears, and a length in excess of 110ly. 

By the early 25th century, the Alpha Quadrant Alliance categorised the region as Syllerran sector, which was part of the larger Vyntadi sector block. 

History
The lost Federation starship USS Voyager traveled through the Nekrit Expanse and visited Riley's Planet in the Parein system on stardate 50614 in the year 2373, passing the Syllerran Rift within circa forty lightyears. 

With the return of the Federation - and the arrival of its allies - to this region of space in 2409, either the Syllerran Rift, the Syllerran system, or both, became the namesake for the Syllerran sector.