The Eastern Counties Railway (ECR) was an English railway company incorporated in 1836 intended to link London with Ipswich via Colchester, and then extend to Norwich and Yarmouth.

The Eastern Union Railway (EUR) was an English railway company, at first built from Colchester to Ipswich; it opened in 1846. It was proposed when the earlier Eastern Counties Railway failed to make its promised line from Colchester to Norwich. The businessman John Chevallier Cobbold and the engineer Peter Bruff were prominent in launching the company. The allied but nominally independent Ipswich and Bury Railway built a line onwards to Bury St Edmunds, also opening in 1846, and soon amalgamated with the EUR.