The Rio Grande runs through Albuquerque for 20-plus miles. Almost all of the land along the river is state park...a long and skinny one, half mile wide at the broadest point. There is a paved bicycle/running/ walking/etc. trail the entire length, with a dirt path for horseback riders. There are several points along the trail to park gasmobiles, and the center point of it is the Albuquerque Biopark (aquarium and arboretum ...the zoo is several blocks away).

We were in Pueblo, CO a couple of weeks ago. They also have a riverwalk...much shorter and less commercially developed than San Antonio's. There is also a 35 mile trail along the Arkansas River, but the section in the city itself is closed for improvements.