Śrīla Bhaktivinoda Ṭhākura writes in a song (Śaraṇāgati 31.3):
gaura āmāra, ye saba sthāne, karala bhramaṇa raṅge
se-saba sthāna, heriba āmi, praṇayi-bhakata-saṅge

“May I visit all the holy places associated with the līlās of Lord Caitanya and His devotees.” A devotee should make a point of visiting all the places where Śrī Caitanya Mahāprabhu performed His pastimes. Indeed, pure devotees of Śrī Caitanya Mahāprabhu even want to see the places He simply visited for only hours or minutes.
(CC Antya 4.211 purport)

Because Kṛṣṇa, Caitanya Mahāprabhu, does not give anything else. Simply directly gives you Kṛṣṇa and His love. And to award this greatest benediction to the human society, He took sannyāsa at the age of twenty-four years only, in this land of Māyāpur, Navadvīpa. It is very glorified place. It is not ordinary place. Therefore Narottama dāsa Ṭhākura says, gauḍa maṇḍala bhūmi, yeba jane cintāmaṇi tara hoy vrajabhūme vāsa. Anyone who understands gauḍa maṇḍala bhūmi in Bengal—this Navadvīpa, Navadvīpa-candra, Śrī Caitanya Mahāprabhu—if anyone understands the spiritual value of this land, he lives in Vrajabhūmi, in Vṛndāvana. There is no difference between Vṛndāvana and this Gaura-maṇḍala-bhūmi. That is the verdict of the śāstra. 
(740302 – Lecture CC Adi 07.02 – Mayapur)