No injuries were reported, and the bridge was not damaged.
Officials said the mast of a sailboat struck part of the Connecticut River Railroad Bridge as it was closing, causing delays on Amtrak's Northeast Regional line.
The Day reported the 41-foot sailboat hit the south side of the bridge in Old Saybrook just after 11:00 am on Sunday. The boat hit the bridge as its operator tried to pass underneath.
Amtrak spokeswoman Kimberly Woods said the incident delayed three trains on the Northeast Regional line between 30 minutes and an hour. No injuries were reported.
Woods said the bridge was not damaged. Amtrak police and the state Department of Energy and Environmental Protection police were at the scene.
The trains were operating by Sunday night.