Port Morris is a largely industrial neighborhood that borders the East River. While much of this neighborhood is devoted to large warehouses and industrial buildings, there are also several blocks of single family homes that are two or three stories and are spaced flush together without front yards. Many of these homes are historic and have beautiful architecture, but their tendency to be dropped among industrial buildings makes this a largely uncomfortable place to walk your dog.
Luckily, this neighborhood offers many diverse walking opportunities that extend past neighborhood walking so that you can find a very pleasant place to walk with your dog. The proximity to Randall's Island State Park offers interesting walking opportunities, as does a wild patch along the river across the railroad.
Be careful that you do not cross into private property along the railroad. Views across the river are of the lovely playing fields of Randall's Island Park, making for a pleasant view as you walk along the shoreline.
While this area does not provide much easy access to the East River, you can cross the train tracks and walk along the Bronx Kill river to enjoy a natural shoreline with your dog. The river is shallow enough in some areas that your dog could wade along the shoreline and the terrain has been allowed to grow wild here.
Across the bridge is the Randall Island Park which is mostly composed of sports fields and amusement park areas that are not necessarily good for walking with your dog, but which also offers walking trails along the Harlem River and the East River that you and your dog will love. These river paths will provide an opportunity for you to walk along the water and enjoy the breezes.
For a little more exploration, you can cross the bridge off of Randall's Island to Astoria Park, for some lovely tree cover walking.
There are several regional parks in Port Morris and the surrounding area where you can escape the cramped city streets. These parks provide pleasant tree cover and nice walking trails to walk your dog on a loose leash. If you would like more extensive greenery, you can head inland towards St. Mary's Park. This expansive park offers rolling green fields for you to run with your dog or play fetch or frisbee.
Natural rock outcroppings provide visual interest as well as offering a good difference in terrain for your dog to explore. Lots of mature trees will make you feel like you are in a natural forest environment. While this park is well-maintained and not wild enough for extensive wildlife, the large amount of tree cover in this otherwise very urban and industrial area provides a safe resort for all kinds of residential and migratory bird life, so you have a great chance of seeing some interesting wildlife in this attractive park.