Start here
http://www.visitpittsburgh.com/ . Explore the 'things to do tab'.
Since it will be your first time there, at the very least, you gotta: 1) Eat at Primanti Bros. - plenty of locations. 2) Ride the Duquesne Incline - It will take you up the hill to Mount Washington(not a mountain) providing spectacular views of the city. Make sure you have a camera! $4.50 round trip. 3) Visit the "Strip District" - It's not what it sounds like
. It's an area northeast of downtown("dahntahn" in Pittsburghese) - Lots of shops, street vendors and great food. 4)If you're into sports at all, go tour Heinz Field and/or PNC Park. 5)Since you'll be there for a week - you gotta do Kennywood Park! Some of the best roller coasters in the world.
I could go on but these are some basics. If you are flying into Pittsburgh, MAKE SURE you are paying attention as you come through the Fort Pitt Tunnel when entering the city - MAGNIFICENT view! I can all but guarantee you will love it. Great people, great food, great town! If only there were Yellowtail in the Allegheny or Monongahela, I might consider moving back
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