Soo 4100 and a CP MP15 are leading the BN Transfer out of the BNSF's Northtown Yard, on their way back to Humboldt Yard. It is a short trip, as both yards are located in northeast Minneapolis. When this photo was taken on April 4, 1998, the 4100 was one of the few Caterpillar units, of the 10-unit fleet, that was in active service. The ten units, 7 GP15Cs and 3 GP30Cs, spent most of their active life switching and on transfer runs around the Twin Cities. They were kept in great condition right up until their retirement. No Soo CATs are running now, with most stored at CP's Ogden Shops in Calgary.