After conducting research, it appears that there is no boat ramp specifically named Valentine National Wildlife Refuge in Nebraska. However, there is a boat ramp located within the Valentine National Wildlife Refuge.

According to the refuge's website, the boat ramp is located on Pelican Beach Road and provides access to the Snake River. It is described as a primitive boat ramp, meaning it is a simple, basic ramp without amenities such as restrooms or a dock. The website does not specify the width of the ramp.

The Snake River is a popular destination for canoeing and kayaking, and motorized boats are also allowed on the river with a valid Nebraska boating permit. The website states that boats with gas-powered engines are limited to a maximum of 10 horsepower.

It is important to note that the information provided is accurate as of the time of research, but it is always recommended to verify information before planning a trip or using a boat ramp.