A Short Guide to Philadelphia
Philadelphia is one of those places where it pays off to carry a compass - or at least to be able to determine the cardinal directions quickly in any other way - at least if you are going to rely on this guide that is.
The city follows the rectangular grid that Manhattan subsequently became famous for; do not get fooled by the common misconception, Philadelphia was the first city on the continent to have this street arrangement. From Delaware River (which separates Pennsylvania from New Jersey) westward streets are enumerated (1, 2, 3, ..., 12, 13, Broad St., 15, 16, ...), and North-South streets were named after trees: Walnut, Chestnut, Pine, ... (and then they run out of trees, I suppose).
Major East-West street is Market St. For the most part it is boring and uneventful, with lots of tall office buildings. Major North-South street is Broad St., in the very center of the city renamed into the Avenue of the Arts hosts several theatres, an opera, buildings of the University of the Arts, a high school for artistically-inclined children, etc. The intersection of the two would be the geographical center of Philadelphia. Here you can find the City Hall, largest masonry structure in the US (larger than the US Congress, for example). The guy on the top of the tower is William Penn, founder of Pennsylvania. Until 1986 a gentlemen's agreement said that no building in Philadelphia shall be taller than Penn's hat - then in 1986 they made Liberty One and hell broke lose. The tower on the City Hall is actually really high, and visits are organized by the Philadelphia Tourist Bureau. The same square hosts a Masonic Temple, there are methinks two tours every day, the information can be found on the door. Northwest of the City Hall, still on the same square, there is the LOVE sculpture ("City of Brotherly Love"), and behind it is the Ben Franklyn Parkway, designed after the Champs Elyses in Paris. Far behind, dominating the end of the Ben Franklin Parkway is the Philadelphia Museum of Art (Sunday entrance free of charge). The Museum of Art should be seen at least from the outside if you do not have the time to go inside, very famous scene in Rocky movies features Sylvester Stallone running up and down the Art Museum steps. Also, Benjamin Franklin Institute of Science, The Rodin Museum, and the Academy of Natural Sciences are also on the Parkway. Half way towards the Museum is Logan Square (actually a circle, with a fountain). Down John F. Kennedy Blvd from the Love Park, in the distance you can see the 30th Street Station, an impressive building in West Philadelphia, over the Schuykill River.
Suggested route: walk down Chestnut St. from the City Hall towards Delaware River (street numbers should be decreasing if you are walking in the right direction). Chestnut and Walnut Streets are very lively, and a pleasure to walk through. On the corner of Chestnut and 6th Street is the Independence Hall, probably the most well known building in Philadelphia. Today dwarfed by the surrounding buildings, at the time it was built it was the tallest building in North America. In 1776 it saw the signing of the Declaration of Independence. In front of the Independence Hall is the pavilion which hosts the Liberty Bell, which was used to mark the beginning of the uprising against the British.
East of the Independence Hall starts the Old City, good to visit at night due to a large number of bars and restaurants, mostly on the expensive side, but not necessarily. SoMa (33 S. 3rd St.) is a bar with a pretty good choice of electronic music. Going north up 2nd Street, you will hit the Christ Church, where Ben Franklin and George Washington used to swing by. A couple of blocks further north, on your right hand side you will find several really narrow streets, one of them being the longest continiously inhabited street in America, and another hosting the building where Betsy Ross sew the first American flag.
Walk towards south along 4th St. The surrounding neighborhood is called Society Hill. Side streets host very pretty buildings, mainly from the XVIII century.
Further south you will hit South Street, which marks the southern boundary of the Center City (Philadelphia downtown). It is generally not advisable to walk past South St., especially at night, although if you know where to go you can find some very charming neighborhoods, such as the Italian Market or Queens Village. South Street is the more alternative part of the town (along South St., from 1st to let's say 10th St.). Places where one can pierce his ears, nose, lips, mouth, throat, nipples and so on are abundant, as are tattoo parlors, book stores and XXX shops. A short walk is sufficient, stopping over for a snack is recommended, as the restaurants in the area are very affordable. Many Brown's is not bad, although it does not look as appealing at first sight. On South and let's say 6th St. there is a restaurant whose name I forgot (all I remember is a painted Bill-Clintonesque face) which makes (unofficially) the best Philly cheese steaks in the city. The officially best place, Geno's, in my opinion is nowhere as good, and is much further down south, in the Italian Market neighborhood. In addition to the cheese steaks, as far as food goes Philadelphia is also famous for hoagies (local name for a sub sandwitch -- the story goes that Italian women carried bread rolls with veggies and cold cuts to their brothers, fathers, husbands etc. who worked on the nearby Hog Island) and Philadelphian soft pretzels. I would recommend some from a food vendor on a street, look for ones that were made in the Philadelphia Pretzel Factory.
Back to the walking tour: I recommend Walnut and Chestnut, west of the City Hall (15 St. and up), on Walnut and 19th is the Rittenhouse Park (free concerts in the summertime). My house was a couple of blocks south from Rittenhouse Square. If you have some time left, walk to 20th and Delancey St. (a little, little street south of Rittenhouse), Sixth Sense the movie was filmed on that block. The Mutter Museum, which is around 20th and Chestnut St. is interesting if you like scientific oddities (skeletons with two heads and so on).
If you happen to be visiting on the first Friday of a month, all of the galleries in Old City (mostly around 2nd and 3rd, Chestnut, Market and above) are open/free to the public, and it usually draws a big crowd. On a nice night, it can be lots of fun.
Alright, this would be sufficient for one day - there is plenty more to be seen, the campus of the University of Pennsylvania in West Philadelphia is worth a visit, as is the surrounding area (University City). Manayunk is also not bad, but it can hardly justify the time necessary to get there. The East State Pen., north of Center City, was the first modern prison, and Al Capone served some time there - they have daily tours.