If you're riding the TRE, you'll want to exit the downtown Fort Worth stop(formerly the ITC), and use one of the buses there. The T&P only has a few routes that service the parking lot under I-30. The downtown station has several bus options. Not familiar with Tex Rail it may have a better option to get to the Stock Yards.
There is a bus stop outside or you can uber. It's only 4.5 miles away
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