It's a densely populated area in the eastern part of the capital, near the Faro Colon monument and the National Aquarium. Easily reached by OMSA-bus service (3 pesos) or taxi (70-80 pesos). I was repeatedly warned not to go there any time of day.
Went there, got to know some really wonderfull folks, and played domino till the crack of dawn. Have been going back there ever since. Overall housing there, except for the "Los Profesionales"-flats, is poor. Hope this helps.