$\Delta$T$_{rms}$$\sim$0.34 K.

Infrared data
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The [**warm**]{} dust distribution was analyzed using high-resolution (HIRES) IRAS data obtained through [*IPAC*]{}[^6]. The IR data in the [*IRAS*]{} bands at 60 and 100 $\mu$m have angular resolutions of 15 and 17.

High angular resolution IRAC images from the Galactic Legacy Infrared Mid-Plane Survey Extraordinaire (GLIMPSE; @benjamin03) at 3.6 $\mu$m (with angular resolution $\phi$ = 15), 4.5 $\mu$m ($\phi$ = 17), 5.8 $\mu$m ($\phi$ = 18), and 8.0 $\mu$m ($\phi$ = 194) obtained with SPITZER were also used. Additional information on IRAC images is available from @fazio04 and from the Spitzer Science Center Observer Support Website[^7].

General characteristics of the complex
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In this section we describe the general distribution of the ionized and neutral gas, while a detailed analysis of some of the most interesting regions will be discussed in the next sections.

Figure 1 shows a composite image of NGC 6357.  is shown in green,  in blue and   in red. The filamentary structure of the ionized gas is evident. In addition to the large shell, clearly detected in   and \[SII\] emissions, the complex shows numerous shell-like features, dust lanes and globules. In Fig. 2 we indicate the location of the most prominent 