**Table 1:** Derived parameters for each of the molecular clouds along the line of sight of LBV 1806-20 and SGR 1806-20, using the ¹²CO(J=1-0) spectra.
Name	W(CO*)^a	$V_{\rm lsr}$ ^b	$A_{\rm V}$	Near distance^b	Far distance^b	Distance^b
	(K km s^-1)	(km s^-1)	(mag)	(kpc)	(kpc)	(kpc)
MC -16	28.4	-14.9	8.6 $\pm$ 1.7	n.a.	24.9	4.5
MC 4	12.7	4.3	3.9 $\pm$ 0.8	0.2	16.6	0.2
MC 13A	32.8	12.7	10.0 $\pm$ 2.0	1.7	15.1	15.1
MC 13B	9.8	16.7	3.0 $\pm$ 0.6	2.2	14.5	4.5
MC 24	18.3	23.6	5.6 $\pm$ 1.1	3.0	13.8	3.0
MC 30	2.6	30.0	0.8 $\pm$ 0.2	3.5	13.2	3.5
MC 38	3.6	38.4	1.1 $\pm$ 0.2	4.2	12.6	4.2
MC 44	5.0	43.5	1.6 $\pm$ 0.3	4.5	12.3	4.5
MC 73	19.8	73.4	6.0 $\pm$ 1.2	5.7	11.0	...^c
MC 87	4.5	87.9	1.4 $\pm$ 0.3	6.1	10.6	...^c
MC 94	1.7	94.2	0.5 $\pm$ 0.1	6.2	10.5	...^c

^a W(CO*) is the integrated line area of the cloud. The error on W(CO*) itself is negligeable compared to the 20% uncertainty we assume to take into account the uncertainties in the various conversion factors for $A_{\rm V}$ .
^b In the text, we use a systematic error of $\pm$ 10 km s^-1 on the velocity of the cloud in order to derive a robust distance range (>2 $\sigma$ ) for each of the molecular clouds.
^c We did not attempt to resolve the distance ambiguity for MC 73, MC 87 and MC 94, since they are between MC -16 and MC 13A in either case.

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