This is rather old, but I just unlocked the ancient training ground and it doesn't appear to have any effect? It costs 1 gpt and 45 production, but has no effects.

@jackmyer37 look at my comment below yours

@Aidanholc the +1 Gold it makes slowly grows over time so when you first build it the output will be -1 but by the time you finish the stock exchange and various other buildings and wonders it could net you +5 Gold a turn

for the farmers market, just make it -1 gpt instead of +1 gpt and then -2 gpt

Why not make Great Medic mode.