i think since you are only there for a really short time you should just head down to the south side and check out the waterworks (at about 19th/20th and carson street) outdoor mall. i highly suggest walking around the mall for a while and then heading down carson to 5th and go to the iguana grill for an early dinner. it's really the best mexican ive ever had.
the waterworks has all your super typical stuff: urban, f21, and the h&m should be open by now.
carson also has a bunch of newer clothing type stores as well. a couple of jeans/denim places. the pittsburgh jeans company is a good place to check out, it's one of the few pittsburgh clothing stores that i have ever seen written up in a magazine ever.
its been a while since ive lived there and ive only been back once in a while to visit my sister who's still there but i hope that helps. have fun, pittsburgh is a pretty cool city. do you know where your bf's parents live? that could help narrow down your options of what to see/do.
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"But I want you to remember, I intend this breast satirically." Susan from Coupling
There really isn't alot of shopping in Pittsburgh, other than the typical mall stores, but the two places I would go to are
1. South Side Works... Which relrel mentioned, they have a website as well that you could check out the different stores there. While in South Side, I would go to Pittsburgh Jean Company, which is on carson street
2. Walnut Street... This is in Shadyside, again they have a website as well... This is more boutiquey type places and a little more upscale. Here I like to go to E.B. Pepper especially.
Other than these two places, the rest of the shopping is mainly different malls, which I don't think would be worth going to if you are only there for a weekend.
If you have never been to pittsburgh before, I recommend going to The strip district saturday morning, its really pittsburghy, because there are all sorts of vendors out on the street, selling all sorts of different things. The view on Mt. Washington is amazing, and you should go up there to see the view ( if looking for expensive restaurants, I highly recommend the Le Mont, my fav pittsburgh restaurant, and has a beautiful view of the whole city) If you don't want to eat, you can grab a drink at the Grandview Saloon to see the view of the city as well.
Another good restaurant is Eleven (in the strip district) and for a quick sandwich you have to eat at primanti bros.
If you have any other questions feel free to pm me... I would be able to give better details if I knew where your bf lives
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"Deep down you may still be that same great guy I used to know. But it's not who you are underneath, it's what you do that defines you" Rachel Dawes, Batman Begins
i love the south side for shopping. shadyside is nice, too..and there are some cute vintage shops on ellsworth (even though i boycott eons because the guys who work there are total bitches).
north of the city, there are some fun shops in sewickley.
in terms of food, i have to recommend my fave restaurant (probably) in the city: kaya. it's in the strip district. in shadyside, i'm also a big fan of giresole. great italian fare in a nice atmosphere (a bit loud, sometimes, though). i love mallorca in the south side...
Great restaurant rec's erin... I love Kaya especially their sweet potato french fries mmmm
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"Deep down you may still be that same great guy I used to know. But it's not who you are underneath, it's what you do that defines you" Rachel Dawes, Batman Begins