Eruv

SYNAGOGUE ERUV LINES
YISE  (301) 593-5561
SEHC  (301) 593-0064
KMS  (301) 593-0996  PRESS 3

Never assume the eruv is up;
Always check before carrying on Shabbat;
Ask your Rabbi what carrying is permitted with an Eruv;
Get detailed information from SSEA if you will be walking near the boundary;