The shortest and most popular is the Broom Hill Summit walk, gently going up Broom Hill (Romulus) beside the lodge, through native mountain beech and wilding hollies, opening up to full 360 degree views over Lakes Grasmere and Sarah to the surrounding mountains, and looking up the Cass River. It takes about 30 minutes return.
The Deer Farm Circuit is a little longer, about 90 minutes, running along the Cass River then following the fenceline round the deer farm which lies up Mt Bailey, through snow tussock and wild matagouri, to a high point overlooking the whole of the station (farm) and neighbouring Cass.
Just down the road, a perennial favourite of about four hours return is the Bealey Spur Track. This climbs through native bush into open tussockland, along a ridgeline with spectacular views over the upper Waimakariri Valley. There are plenty of places for picnics, beside alpine tarns or at the old mustering hut that was used in the past by shepherds overnight.
With thanks to the NZ Department of Conservation for some of this information.