From The Bus and Coach Station:

Leave the Bus Station through the glass doors by the large clocks. Walk down the lane and then down the steps to the street. At the bottom, cross over the main road in front of you (towards the shops opposite the House of Frazer). Walk along the Horsefair and keep following the road past the building site until you come to a park on your right and the Marriott Hotel on your left. Keep walking past the hotel and the road bends round and meets a roundabout.

Cross the roundabout (there is a pedestrian way through the central reservation), and go straight ahead into Old Market Street. Cross to the left-hand footpath and walk along to the traffic lights (at a crossroads). Carry straight on past the Palace Hotel and about 50 yards further on along West Street you will see Gloucester Lane on the left. The Old Castle Green is the second building on the other side of Gloucester Lane.

Walking time around 15 minutes.