The Children of Green Knowe
by L. M. Boston
Sort like the Gothic version of Burnett’s The Secret Garden, this book (and the rest of the Green Knowe series) has always been my favorite and is one of the best kids’ books featuring ghosts and echoes of the past with slightly creepy manorial settings where mysteries abound. Everything from Alan Garner’s The Owl Service to Tony DiTerlizzi and Holly Black’s Spiderwick Chronicles owes something to this work or seems to be inspired by it. I know that for sheer atmosphere, it’s incredibly evocative.