  The observation and imaging of hundreds or thousands of radio sources with
the technique of very long baseline interferometry (VLBI) is a computationally
intensive task. However, these surveys allow us to conduct statistical
investigations of large source samples, and also to discover new phenomena or
types of objects. The field of view of these high-resolution VLBI imaging
observations is typically a few arcseconds at cm wavelengths. For practical
reasons, often a much smaller fraction of the field, the central region is
imaged only. With an automated process we imaged the ~1.5-arcsec radius fields
around more than 1000 radio sources, and found a variety of extended radio
structures. Some of them are yet unknown in the literature.
