Hey Laharkisawari: 
I have lived away from my family for about 6 years now. Every time I go to visit my family, which is just my Mom, Dad, and Grandma, my Mom feels the need to block me from spending time with my grandma. I really find that my grandma and I resonate. I did not really get to know her until I was a little bit older and my Grandfather had passed away
Does your grandma live with your parents now? How old were both you and your grandma, when you first got to know her? Could your mom be trying to protect you from some things she experienced with your grandma?
My Mom feels very strongly that she did not have the best childhood and she resents my Grandmother for it. My Mom has gone into counseling to talk about her past traumas, or at least that is what she tells me, but It seems that she and my grandmother just can't even be in the same room without my Mom wanting to scream at her.
Has your mother shared any details of what "not having the best childhood" means to her? Does your mom think that your grandma has a personality disorder?
I am just a little stunned at how my Mom acts toward every visit I have. She acts like I am only coming to see her. She actually will plan out the whole trip, minute to minute(for real), and say that she knows I like to sit inside and not be too busy, and spend time at home. In all actuality I love being outside, I love going on walks, I love exploring new places and meeting new people.
Perhaps you might want to negotiate a compromise. If you visit for a weekend, you might dedicate one day to what your mom wants and then do some things you want on the other day. Work in a walk. Suggest eating one meal outdoors. Evolve over the course of a few visits to make part of the visit the way you want it.
If the visit is for the upcoming weekend, you might bring up something like a walk in advance. Is there some place near your parent's home, where you would like to walk (a park, a nature trail, around the neighborhood)? Maybe during the upcoming visit, you bring up the subject of something you would like to do on the following visit.