Al-Firdaus is the highest of Paradise

The Prophet (ﷺ) said

 "Al-Firdaus is the highest of Paradise and its most expansive, and 

Above that is the Throne of Ar-Rahman (the Most Merciful), 

and from it the rivers of Paradise are made to flow forth. So when you ask Allah, ask Him for 

Al-Firdaus." 

Jami at-Tirmidhi Hadith 2530