Bulls, buffaloes, dogs - some with collars - birds, elephants, squirrel, monkeys and more. All made of terracotta and dating back to the Harappan age are being showcased at a special exhibition at Indian Museum to mark World Heritage week and Children's Day.

Harappan Toys, which opened on Monday, has on display 12 artefacts in terracotta, including toy animals - buffalo and humped bull, wheels of toys and miniature utensils such as tumblers, pitchers and jars with lids. The exhibition will remain open from 10am to 5pm daily till Sunday.

The Harappan sites, covering a huge geographical terrain, number around 1,022. Of them, 616 are in India and the rest in Pakistan. They date roughly from 3200 to 1900 BCE.

Among the rich archaeological evidence of life in these ancient settlements are several toys made of terracotta and shell. It is evident that the Harappans loved their children and made amazing objects for their amusement.

There were animal and human forms with eyelets where movable arms and legs and heads could be attached. Tiny masks with perforations for strings to be attached could have been used for puppets. Terracotta whistles and tops (one of them tipped with copper to make it turn longer) and terracotta carts with holes where strings and tiny sticks could be inserted to make them run like real carts have been found. Terracotta marbles and discs of different sizes are remnants of games they played. Miniature terracotta cooking utensils and furniture may have been used to play house.

The exhibits are only a small part of the mammoth and rare collection at the museum. The pre and proto history gallery once located on the ground floor of the museum was shut for renovation some 15 years ago. Since then no one has been able to view the objects, including stone-age tools, pottery and figurines.

Sayan Bhattacharya, an archaeologist and education officer of the museum, said a new gallery is being readied on the mezzanine floor. Finds from excavations at Harappa count for a large share of the collection.