Described herein is an animal pen (1) including a gate (6) with a structural frame (7). The gate structural frame avoids use of a cross-beam at the foot of the frame thereby avoiding issues associated with such beams including trip hazards and animal fear issues associated with such cross beams. The frame includes additional stiffening elements to compensate for the lack of bottom the bottom cross-beam. The frame design also minimises permanent damage to a substrate and can be installed and uninstalled relatively quickly with simple tools such as a spanner and fasteners.