Complex sentence: Idukki district alone has about 50 small or big waterfalls most of which are not included above because of not being well known and some are only active during monsoons.Same with Wayanad district, Pathanamthitta district and other hilly districts.
Split into simpler sentences: Idukki district alone has about 50 small or big waterfalls, most of which are not included above because of not being well known and some are only active during monsoons. It is the same with Wayanad district, Pathanamthitta district and other hilly districts.