In which castle was Mary, Queen of Scots executed?

Player #2342698, she was executed by Elizabeth 1, she was her cousin and had designs on the throne. catholics plotted to put her on the throne, Elizabeths minsters thwarted the plot so curtains for Mary.

Murdered you mean! Mary had a genuine right to the throne of England. They just couldn't bear to have a Catholic reign again, so invented some plot that she unwittingly got drawn into.

why was she executed?? give more important info!!