Tucked out of sight at the back of 25-27 Gray Street, this is a townhouse that feels like a house unto itself. Its private front entrance sits quietly down the drive, removed from the street, while at the back, glass doors open directly from the living room into a fenced garden of its own. There is a sense of privacy here that is unexpected in the middle of Cambridge, and a completeness to the way the house lives that is rare.With three bedrooms, four and a half baths and garage parking, the home unfolds over four levels with an abundance of windows and natural light. But it is the connection to the outdoors that makes it especially compelling. Throw open the living room doors and the space spills naturally into the garden, with a pretty stone patio for dinner outside, lawn, mature trees and garden beds. On the third floor, a treetop deck offers a completely different perspective, perched above the garden and looking out across the neighborhood.And for all its privacy, the location puts so much of Cambridge life close at hand. Mornings might begin with coffee along Mass Ave, afternoons around the Radcliffe Quad, evenings at Giulia or wandering into Harvard Square. Surrounded by the University, cafs, restaurants, bookstores and green space, it is a neighborhood where daily life develops its own easy rhythm, with home waiting quietly just down the drive.