Generously salt and pepper the inside cavity of the chicken, and add 4 rosemary sprigs, thyme, garlic, and half of the lemon. Slice the remaining lemon half into thin slices and slide them under the exterior skin of the chicken breasts. Take the remaining 2 rosemary sprigs and slide them down along each side of the breast bone under the skin. Tuck the wings back and under the chicken and tie the legs together for even cooking.
Place the chicken, breast side up, on a rack in a roasting pan and brush the top and sides with olive oil. Sprinkle with salt and pepper.
Roast chicken in the oven, basting with drippings at least once, until juices run clear and leg bone easily pulls away from the meat, about 1 hour 15 minutes to 1 hour and 30 minutes.
Remove chicken from oven and cover with foil. Allow to rest for juices to redistribute, at least 15 minutes.