Students and seniors frequent this basic, wonderfully inexpensive chain property (it was a Comfort Inn until Holiday Inn refurbished and reopened 2013).  Hemmed in on all sides by major arteries—it's on busy Columbus Boulevard, with I-95 right behind it and the Ben Franklin Bridge half a block to the north—it does feel a bit isolated, but you're actually only a short walk from Penn's Landing or any of the Old City sights, just 3–5 blocks away. The hotel also offers a free shuttle anywhere out to a 20-block radius. Nice. 

However, heavy doors and soundproofed windows can't quite drown out the roar from all those busy roads; rooms on the front are at least a bit quieter than those facing I-95, and as a bonus they come with river views.  But the rates are among the cheapest in town, there's free WiFi and complimentary breakfast, and the staff are (generally) notably helpful and friendly.