(Undated)  --  Neighborhoods around Portland are holding events for National Night Out tonight.  Dozens of parties are planned in the Portland area.  The annual event takes place the first Tuesday of each August and hopes to build stronger ties between police and the communities they serve.  National Night Out has been taking place for 35 years.  Many neighborhoods host block parties and cookouts and give police a chance to interact with the public in a non-official manner.