We had an absolutely fabulous meal at Estia last summer. I can highly recommend it.

http://www.estiarestaurant.com/index2.asp

SusanCS,
Estia looks great!!! But I couldn't find any prices on their website. It looks pricey! Could you give me an idea of what the meals cost?
Thanks.

Would definitely recommend a board search, as there are plenty of threads on local food (including some large ones on cheesesteaks).

I too really liked Estia the time I went -- really excellent. It's not cheap, though, but given that it's possible to drop a lot of money and get a bad meal, this should at least give return on your financial layout.

There's really not a lot in terms of distinctive "neighborhoods" for walking in Philadelphia (like one would find in San Francisco) aside from Chinatown and perhaps the Italian Market.

As for "can't miss" stuff, we'd need to know what you like to do. Have been to the Rodin Museum, Liberty Bell, and the historic buildings in the Independence Mall area and can say I really liked all of these attractions very much. Was less taken with the Constitution Center, but that's in part because it didn't tell me a lot I didn't already know; it did present information in a clear and easy-to-digest manner and may be a must for some folks.

How about drawing up a possible itinerary with the things you'd like to include and then submit it for suggestions?

I think that the Eastern State Penitentiary is a cool place to visit. http://www.easternstate.org/

If you have a strong stomach, there's always the Mutter Museum. http://www.collphyphil.org/MUTTER.ASP

The Phila Museum of Art is world class and always worth a visit.

We had a great meal at Tinto last NYE. Jose Garces is the new "Iron Chef" and has a number of restaurants in the city. Amada is a great tapas restaurant of his. http://grg-mgmt.com/

There is a wine bar called Tria that has great small plates and wine by the glass as well as some interesting beers. There are 3 locations I think. http://www.triacafe.com/

El Vez is a cool campy mexican place - not the best mexican ever, but the setting is interesting. It's a Stephen Starr restaurant. All of his places are different and the food is usually good to very good. http://www.starr-restaurant.com/

Take a walking tour of the Historic Area. Go the Visitors Center first to get your timed tickets for Independence Hall (you can also get them on line in advancea). The Visitors Center will provide a lot of information and you can just follow one of the walking tours they have mapped out.
Make sure to see Franklin Court. There is a small interesting museum there also and the cemetery with Ben Franklin's grave.

For food suggestions, try this thread
http://www.fodors.com/community/united-states/and-nowthe-100-best-things-to-eat-in-philadelphia.cfm

If you are interested in archeology, the University of Pennsylvania's Museum of Archeology and Anthropology has a very good collection.

Among the more interesting restaurants in Philadelphia are the BOYBs. Because of the difficulty and cost of obtaining liquor licenses, there are many places which offer excellent dining and allow you to bring your own wine. Most do not charge corkage. And there are a few which allow you to bring your own tequila; you may then purchase a pitcher of their margarita mix.

Our current favorite BYOBs are Matyson, Bibou, Melograno, and Branzino. Matyson and Bibou are small (32 to 40 seats); the other two, somewhat larger. Reserve early!

www.matyson.com
37 South 19th Street

http://www.biboubyob.com/
1009 South 8th street

http://www.melogranorestaurant.com/
2012 Sansom St

www.branzinophilly.com
261 South 17th Street

Estia is also a terrific choice. Take a look at the pre-theater menu and business lunch menu if you want to keep costs in line.

Other places you may want to consider are Osteria and any in the Jose Garces group (Amada, Tinto...).

http://www.osteriaphilly.com/

http://grg-mgmt.com/

Enjoy your visit to Philadelphia!

Without knowing your interests and trying not to repeat. . .

The Dream Garden at the Curtis Center
The Magic Garden on South Street
Washington Square
Rosenbach Museum (rare books and literature)
Aftican American Museum
Balch Institute for Ethinic Studies
Historic Churches in Society Hill and their cemetaries
Pennsylvania Academy of Fine Arts
Chemical Heritage Museum
National Liberty Museum
Fireman's Hall
Museum of American Jewish History
Swedish Historical Society
German Society
Poe House
Mummers Museum
Seaport Museum/Ships at Penns Landing/Drive around Navy Yard
Elfreth's Alley
Mural Arts Tour
Atwater Kent (Philadelphia history)

Other Neighborhoods Worth a Walk: Society Hill (colonial history); Northern Liberties (Eastern rite churches, 19th century architecture, gastropubs and funky stores); Old City (art galleries); Rittenhouse Square (architecture, particularly southwest of the square); Wash West (dining, small cobblestone streets).

Hope you don't run into this:

http://www.philly.com/philly/hp/news_update/20100322_Another_flash_mob_rocks_South_Street__In_the__tsunami___chants_of__Burn_the_city__.html

For neighborhood walking, the 13th/Locust area has some great shops and neighborhood vibe: duross and langel (soaps/body stuff), Capogiro Gelato, Naked Chocolate Cafe...mmm.

I like the Rittenhouse Square neighborhood for wandering, too, and then of course there's Manayunk and Chestnut Hill/Germantown and Northern Liberties and...well, check here:
http://www.visitphilly.com/itineraries/

Here's a thread with a lot of help, including a link to the "Franklin Walking Tour" (and a lot of other links, too):
http://www.fodors.com/community/united-states/advice-on-philadelphia-itinerary.cfm

and my all-time favorite Philadelphia trip report (with good restaurant info in it, too):
http://www.fodors.com/community/united-states/philly-pfriends-pfood-an-overly-verbose-trip-report.cfm

Have a wonderful time! (Are you sure you can only have four days? )

Thank you so much to everyone who replied!!! We love history, museums, interesting neighborhoods, good food, parks, markets, etc. so I think you all have covered what we like to do.

I will check out the various links everyone supplied.

Bachslunch writes "There's really not a lot in terms of distinctive "neighborhoods" for walking in Philadelphia (like one would find in San Francisco) aside from Chinatown and perhaps the Italian Market."

I disagree with this statement, finding Philadelphia equally as good a walkers city for distinctive neighborhoods as San Francisco... with plenty beyond Chinatown and the Italian Market. I think Chinatown and the Italian Market are fun for a stroll true, but MLTimes' post (Society Hill, Rittenhouse Square, etc.. )and Amy's post (Manayunk) right after expand on some additional favourite areas of mine. I'll add the Gayborhood (lots of antique shops and early-13-colonies style)and mention that I also enjoyed strolling through the UPenn campus, eating at an excellent pub/restaurant (called something Dog?) there when I went for an interview a number of years back.

Have fun! Daniel

Daniel,
thanks for adding the tip about Gayborhood. Sounds like our cup of tea. I will print out everyone's responses. I can't wait to go!
karen

Laughing here - was about to contribute but Amy beat me to it, and can't appear to be too overly narcissistic to think I could help, 'twould be unseemly... These recs all look fabulous, I'm jealous of your trip and wish you the best. Listen to Amy, she knows her stuff!

(back to my Budapest report...thanks for the props, Amy )

Karen, Amy and Daniel -

I'm going to pull some Philly atty-tude here and claim credit for being first to mention the Gayborhood, which I referred to by its alternate name "Wash West" (and also aka "Midtown Village").

And if you like that type of vibe, I'm going to re-recommend Northern Liberties. Especially for food. Koo Zee Do, a portugese restaurant, is the new darling, but the gastropubs (eg, N.3d) and the brunch spots (Honey's Sit & Eat) are some of the best in the city.

Also, for brunch, especially if you want to stop as you drive out of town, I am absolutely re-loving Cafe Estelle recently on 4th right above Callowhill. It's walkable from No. Libs and Old City, but good if you're driving bc it has a parking lot.

I would highly recommend a Phillies game if you are baseball fans. Great park and always fun.

Daniel,

The restaurant you're thinking of is White Dog.

Thanks, MLTimes, for clarifying that Gayborhood is AKA Wash West. Otherwise, I might be confused & think I missed one of them.
Thanks everyone for all your wonderful suggestions.
Karen