<font face="Verdana, Arial, Helvetica, sans-serif" size="2">Originally posted by kv99:
Typically, it's a very nice walk, but I'd say a cab could be in order in mid-March, when the weather is not always so great in Philly. Or maybe you guys know a different Philadelphia than me. 
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Well, I'd venture that the cab ride and walking probably will take about the same amount of time outside of rush hour, and the cab might take longer during rush hour.
To avoid the weather, you can also walk the entire way underground - the subway concourse in front of the PH runs under Broad and Market all the way to the Convention Center. Actually, the concourse is quite extensive - it runs under Market/JFK from 7th to 17th and under Locust from 12th to 16th.
Not that I would suggest walking in adverse weather if your company is picking up the tab...