Unfortunately, once again, it does NOT look as though Hyndburn has anything to offer for Heritage Weekend - (correct me though if I am wrong) so ... the next best thing is the BURNLEY area. They have the most WONDERFUL events planned. In particular you should try Towneley Hall. I went last year and its absolutely marvellous. In a strange sort of way I even fancy the Crematorium - which is being opened to the public.
http://visitburnley.com/wordpress/wp...ys2013_Web.pdf
http://visitburnley.com/wordpress/wp-content/uploads/downloads/2013/08/REDU_TIC_HeritageOpenDays2013
Do scroll down to the bottom of the site, as it does give much more detail about the events planned.