In which region has the ancient water harvesting structure 'Kulhs' been established ?

Options

A. Rajasthan
B. Maharashtra
C. Bihar
D. Himachal pradesh

Explanation

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks about the region where the ancient water harvesting structures known as 'Kulhs' have been established.

2. **Defining Kulhs**: Kulhs are traditional water harvesting systems that involve diverting water from streams into man-made canals. This system allows water to flow down to various villages situated on hillsides.

3. **Identifying the Region**: The Kulhs system is primarily associated with the region of Himachal Pradesh in India. This state is known for its hilly terrain and the use of such ancient water management techniques.

4. **Conclusion**: Based on the information gathered, the answer to the question is that the ancient water harvesting structures 'Kulhs' have been established in Himachal Pradesh.

### Final Answer:
The ancient water harvesting structures 'Kulhs' have been established in Himachal Pradesh.

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