Why my map is so lag, so slow ??

Q: why is my map lagged
basically it depends on the "how much do i have" and the "how do i make Little of it"

how much objects do you have?
instead of LOTS boxes side by side (next to each other) just make one big rectangle and apply decals to the object!

to much complex models?

how big is the map?

is there a leak?