The Luni-Solar Calendar is the oldest known Indian calendar, dating back to the 2nd millennium BCE.

The Vikram Samvat calendar is a lunisolar calendar, meaning that it is based on both the lunar and solar cycles.

The Shaka Samvat calendar is a solar calendar, meaning that it is based on the solar cycle.

The Hindu calendar is a lunisolar calendar, meaning that it is based on both the lunar and solar cycles.

The Indian national calendar is a solar calendar, meaning that it is based on the solar cycle.

The Indian calendar has 12 months.

The Indian calendar has 365 days.

The Indian calendar has 4 leap years in a cycle of 100 years.

The Indian calendar has 30 festivals.

The Indian calendar is used in India, Nepal, and Sri Lanka.

The Indian calendar is both a religious and civil calendar.

The Indian calendar is a lunisolar calendar, meaning that it is based on both the lunar and solar cycles.

The Indian calendar has 12 months.

The Indian calendar has 365 days.

The Indian calendar has 4 leap years in a cycle of 100 years.