I'll admit I looked at baseball reference for this one - because I was curious how many HRs Sosa hit at home (321-288) compared to Ernie Banks (290-222), and the numbers are very, very close. 293 to 290. Then I looked at Mel Ott because I read somewhere he hit 2/3 of his HRs at the Polo Grounds. It's a big number, maybe the most by any player.
Sosa spent some time with the Sox. His total Wrigley is 293. Ott is correct as the all time leader in HR in one ballpark - he hit 323 in the Polo Grounds. Ruth, curiously, hit more HR on the road than at home - probably sober less often at home. He also played with Polo as a home park for a few years with the Yankees, including his monster 1920 and 1921 cards.
Bruce is correct for Cincy. Neither Bay nor Alvarez are the HR leaders at PNC. Bay had 61 there, Alvarez 62. McCutchen has 83.
This is probably the toughest of the 6 divisions, one of the players involved is not in the ATG set and another is used very rarely in my experience.
And which park has yielded the most HR to one individual? This is closer than you think, the top 3 parks here have allowed 166, 160, and 157 HR to their leaders.