Extremely dirty and dismal place to visit. There are beautiful areas on the island however extremely limited. If you take a tour do it through the cruise company rather than going alone. The downtown area is a few minutes walk from the cruise ship but broken sidewalks, broken sewers and unsavory, unfriendly people everywhere.
Also, the Dominican Republic is similar. The new port area at Santo Domingo is beautiful, however it is advised not to go out alone or in small groups from this port secondary to safety concerns. The tours are extremely cheap for a reason in Santo Domingo.