This is Calamari's model, but with some changes done to make the model easily printable without supports. I started with Calamari's model because it has such nice detail in most of the model.
In particular, each of the four minarets has three observation decks. Under them were cylindrical projections that represent decorative elements in the original structures. The way these are placed, they're accurate to the original structure, but impossible to print without supports, so I've eliminated them. At the same time, I added slopes on the undersides of the decks to smooth out the overhang (the original structure has fluted, decorative eves, so this fits anyway).
I added slopes under the eves of the chhatris at tops of the minarets, and gave a similar treatment to the four larger ones surrounding the large dome on the roof of the main tomb.
I've thickened up the walls around the minarets' upper observation decks a little bit (Slic3r kept splitting them into many small pieces). The spires at the tops of the domes don't render well, being so thin, but I can't thicken them without distorting the model.
There are still some non-manifold polys here and there, but not enough to cause Slic3r to mess up the model.
Printer:
Prusa i3
Rafts:
No
Supports:
No
Resolution:
0.2 mm
Infill:
15%
Notes:
Use a wide brim at the bottom of the model - the round "corners" under the four minarets may want to lift off of the build plate, even with good filament and clean glass.
The pictured print was done with with Atomic "Perfect Orange", 0.4mm line width, 60 mm/sec, 45 second minimum layer time, and lots of airflow. Print time was about 11½ hours.
I feel the need to point out one thing: to be accurate to the original building, the four domed chhatris on top of the main building/tomb, and the smaller ones that form the tops of the minarets should all have been eight-sided, rather than six, but doing so would have made them too fragile to print.
