If we can add buildings, then I'll add a National Park, with 19 forest preserves, which power 19 engineers/angkor wat priests, with the levy above, for a base hammers of:
5+9+38 = 52.
If you want to count in bonuses and stuff as well, then you can get:
+25% (forge), +25% (factory), +60% (Shale Plant - good thing you don't need coal!), +50% Iron Works (don't get the full bonus), +10% state property for +170% total, yielding:
52 * 2.7 = 140 hammers per turn (not counting bonuses for building units/buildings, access to stone for a wonder, etc...)
5+9+38 = 52.
If you want to count in bonuses and stuff as well, then you can get:
+25% (forge), +25% (factory), +60% (Shale Plant - good thing you don't need coal!), +50% Iron Works (don't get the full bonus), +10% state property for +170% total, yielding:
52 * 2.7 = 140 hammers per turn (not counting bonuses for building units/buildings, access to stone for a wonder, etc...)