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The stellar content of the southwestern photodissociation
region in M17 - the "Arc" - has been studied by multicolor
imaging and infrared spectroscopy. We find a small aggregate of
deeply embedded young stars many of which show evidence for
circumstellar material. The new data resolve several important objects into
multiple components which were previously treated as single sources.
Additionally, we detect a number of cometary- or elliptical-shaped
emission nebulae in the immediate vicinity of young stellar objects.
The ultracompact HII region M17-UC1 is elongated at 2.2 micron
suggesting a binary source of almost equally bright components or a
cometary shape. The silicate absorption feature of M17-UC1 indicates
a visual extinction of 40 mag. The nearby bright MIR source IRS5
consists of three objects with IR-excess; the major component is an
X-ray source, the reddest component coincides with a maser source.
Another very red source in the region is surrounded by circumstellar
dust and is associated with a H_2O maser. Several cometary-shaped
objects of unknown nature are presented. From all this evidence we
conclude, that the Arc represents one of those regions in M17 where
the nearby O-stars have triggered a new generation of massive stars.
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