The state in India that is famous for its backwaters and houseboat cruises is Kerala.

Kerala, also known as "God's Own Country," is located on the southwestern coast of India. It is renowned for its beautiful backwaters, which consist of a network of interconnected canals, lakes, rivers, and lagoons that run parallel to the Arabian Sea. These backwaters span over 900 kilometers, making them a major tourist attraction in the state.

Backwaters:
- The backwaters of Kerala are formed by the merging of several rivers that flow through the state, such as the Periyar, Pamba, and Meenachil.
- They are a unique ecosystem that supports a variety of flora and fauna, including several endangered species.
- The backwaters are lined with lush greenery, coconut palms, and traditional villages, offering a serene and picturesque landscape.
- They serve as a major transportation route for local communities, with traditional houseboats known as "kettuvallams" being a popular mode of transport.

Houseboat Cruises:
- Houseboat cruises are a popular way to explore the backwaters of Kerala. These houseboats are traditional rice barges that have been converted into luxurious floating accommodations.
- They offer a unique experience, allowing tourists to leisurely cruise along the tranquil backwaters while enjoying the scenic beauty and serenity of the surroundings.
- Houseboats come in various sizes and offer modern amenities such as bedrooms, bathrooms, living areas, and even kitchens, providing a comfortable and luxurious stay.
- The cruises typically include delicious traditional Kerala cuisine prepared on board by experienced chefs.
- Visitors can choose from different routes and durations for their houseboat cruise, ranging from a few hours to several days, depending on their preferences.

Tourist Experience:
- Kerala's backwaters and houseboat cruises attract tourists from all over the world who are seeking a unique and relaxing experience amidst nature.
- The backwaters offer a peaceful and tranquil environment, away from the hustle and bustle of city life.
- Tourists can witness the daily life of the local communities living along the backwaters, observe traditional fishing techniques, and interact with the friendly locals.
- The houseboat cruises provide an opportunity to unwind and rejuvenate while enjoying the breathtaking views and the soothing sounds of nature.

In conclusion, Kerala is famous for its backwaters and houseboat cruises, offering tourists a memorable and enchanting experience amidst the serene and picturesque landscapes of the state.