The route between the Resort Area and Stark Mountain. It works very well for me.
elite 4
i trained mine at mt.cornet
route 205 for Pokemon diamond, pearl and platinum. the trainers have Pokemon from level 10 to level 17
the place where you can breed Pokemon next to heart-home city, that's where i go
Route 201 or 202 or 203
elite 4
I don't think it's possible to get a cranidos in Pearl.
Eterna Forest.
iron island or upper level mt coronet
An area with grass Pokemon would be best.
If you're a member, rock crabs are your best option.
Snover evolves at level 40 in Pearl.