Ellis Cottage, erected 1865, is made of local uncut stone. The cottage is a typical farmers residence of the 1870's. The stone construction is unique in this district as most construction is weatherboard.Nillumbik Historical Society is the custodian of historic Ellis Cottage which began being built in late 1865 by William Ellis. On Sunday 22 March, 2015 the Society held celebrations there to commemorate the 150th Anniversary of Ellis Cottage.The Society houses a large collection of historic photographs and documents of pioneering families from Diamond Creek and its surrounds. Ellis Cottage at 10 Nillumbik Square, Diamond Creek is open the first Sunday of every month, except January from 2 pm – 4 pm or by appointment.