Now
MARTA
To get to Grant Park using MARTA take the East/West line to the King Memorial Station and catch the southbound 32 or 397 bus depending on whether you want to go to the east or west side of the park.
On Foot
The map below shows the most direct walking route from the train station. I wouldn't recommend walking from much further than that. Be sure not to miss Historic Oakland Cemetary on your way.
Car and Bike
By car or bike, Boulevard is generally your best bet. It takes you right along the east side of the park and straight to parking for the Zoo and Cyclorama.
From I-20, head south on Boulevard until you see the park on your right.
Then
Street Car
From downtown, take the Mitchell St. line east to the Cherokee Ave. line and ride south to the park.
Street Car Lines Near Grant Park
"Nomination for Inclusion in the National Register of Historic Places for Midtown, Atlanta." Sometime after 2004. September, 2008 Courtesy of the Atlanta History Center