One instrument mounted on Columbus was ISS-RapidScat, and this graphic shows the location of Columbus and where that instrument was mounted on the Module. The instrument was installed in 2014 and operated until 2016.
The European Space Agency has spent €1.4 billion (about US$2 billion) on building Columbus, including the experiments that will fly in it and the ground control infrastructure necessary to operate them.
The laboratory is a cylindrical module with two end cones. It is 4,477 mm (14 ft 8.3 in) in external diameter and 6,871 mm (22 ft 6.5 in) in overall length, excluding the projecting external experiment racks. Its shape is very similar to that of the Multi-Purpose Logistics Modules (MPLMs),
since both were designed to fit in the cargo bay of a Space Shuttle orbiter. The starboard end cone contains most of the laboratory's on-board computers. The port end cone contains the Common Berthing Mechanism.