12 main forests in the Braja Mandal

On the eastern bank of the Yamuna
are five forests called

1. Bhadravana, 
2. Bilvavana (Belvan), 
3. Lohavana (Lauhavana), 
4. Bhandiravana and 
5. Mahavana.

On the western side of the Yamuna
are seven forests which are:

1. Madhuvana, 
2. Talavana, 
3. Kumudavana, 
4. Bahulavana, 
5. Kamyavana, 
6. Khadiravana, and 
7. Vrindavana.

Of the 12 main forests, the forest of Vrindavana is considered the most important. These 12 forests are visited on Braja Mandala parikrama.

More
http://en.brajdiscovery.org/index.php?title=Vanas_of_Braj

This is similar to the twelve cantos of the SRIMAD BHAGAVATAM which are compared to the different parts of Krishna's transcendental form.

• First and second cantos are Krishna's lotus feet; 
• Third and fourth--Krishna's thighs; 
• Fifth—Krishna's chest; 
• Seventh and eighth--Krishna's arms; 
• Ninth-Krishna's neck; 
• Tenth—Krishna's smiling face; 
• Eleventh-Krishna's forehead; 
• Twelfth-Krishna's crown.

Then there are The 24 Upa-Vana are:- 

1. Gokula, 
2. Govardhana, 
3. Varsāna, 
4. NaṅdaGrāma, 
5. Saṅketa, 
6. Paramadra, 
7. Aḍīnga(Aringa), 
8. Sessai, 
9. Mat, 
10. Unchagram, 
11. Kelavana, 
12. Śrī Kuṇḍa, 
13. Gandharvana, 
14. Parsoli, 
15. Bilchhu, 
16. Bacchavan, 
17. Ādibadri, 
18. Karahla, 
19. Ajnokh, 
20. Pipāṣa-Vana (Pisaya), 
21. Kokilāvana, 
22. Dadhigrāma, 
23. Kotavana, and 
24. Rāvala.