Pittsburgh parallels converge, where five plus six equals one

 From a map of Pittsburgh's "Golden Triangle", if dim but serviceable here....

 a closer look, as in so many cities, shows the routine site of numbered streets running parallel to each other - with specific reference here to Sixth and then Fifth Avenue two streets below that (with both of them visible under the "WOOD STREET" notation)....

but looking again at what's above, you will see that Sixth Avenue takes a turn for the weird below the right center of the map and intersects Fifth Avenue, with that encounter seen below in the flesh, or at least stone, glass and more, and where the tunnel to the right above Sixth Avenue - if built long after this strange meeting - makes me think that, in combination with nearby freeways, hasty urban renewal may have seen this latter part of Sixth Avenue as just a "pass-through" unworthy of renaming ....

looking west on 5th Avenue towards the intersection of 5th and 6th Avenues, Th., Jan. 3, 2013

On the other hand, I feel we have too few weirdnesses like this, so I'll take it! And whether it is an old or new story, it is even better in being graced by one of the great works of American architecture - the now ex-jail of the 1888 complex designed by Henry Hobson Richardson for the Allegheny County Courthouse - at its southwest corner, and partly seen here....

with one final view for now at the corner and more of the "Richardsonian Romanesque" landmark off to the left....