In the Neolithic period, Newgrange continued as a focus of some ceremonial activity. New monuments added to the site included a timber circle to the south-east of the main mound and a smaller timber circle to the west. The eastern timber circle consisted of five concentric rows of pits. The outer row contained wooden posts. The next row of pits had clay linings and was used to burn animal remains. The three inner rows of pits were dug to accept the animal remains. Within the circle were post and stake holes associated with Beaker pottery and flint flakes. The western timber circle consisted of two concentric rows of parallel postholes and pits defining a circle 20 m in diameter.
A concentric mound of clay was constructed around the southern and western sides of the mound and covered a structure consisting of two parallel lines of post and ditches that had been partly burnt. A free-standing circle of large stones was constructed encircling the mound. Near the entrance, 17 hearths were used to set fires. These structures at Newgrange are generally contemporary with a number of Henges known from the Boyne Valley, at Newgrange Site A, Newgrange Site O, Dowth Henge and Monknewtown Henge.
*Thanks to Wikipedia for this description*