holy places

The Garuda Purana enumerates seven cities as giver of Moksha.
A Kṣetra is a sacred ground, a field of active power, a place where Moksha, final release can be obtained.

Moreover, Mathura is one of the seven most holy places for Hindus in India.

Rest six are:

1. Ayodhya

2. Māyā (Haridwar)

3. Kāsi (Varanasi)

4. Kāñchī (Kanchi)

5. Avantikā (Ujjain)

6. Puri (Puri)

7. Dvārāvatī (Dwaraka)