Find out the structures similar to megaliths or commemorative memorials in other civilisations of the world. List the similarities and dissimilarities between the megaliths and these structures.

Some structures similar to megaliths or commemorative memorials in other civilisations of the world are:

1. Newgrange site of Ireland
2. Gobekli Tepe of Turkey
3. Malta's megalithic temples
4. Stonehenge of England
5. Pyramids of ancient Egypt

Similarities:

1. They all are of neolithic period, built around 3000 BC to 2000 BC.
2. All are stone structure, made without using mortar.

Dissimilarities:

1. The differ in their height, shape and size.
2. Some have erect stones (pillars) while others have flat stone pieces. Stepped stones were used in pyramids.
3. Some of them are dome shaped (like Newgrange of Ireland), while a few are long barrow type(tumulus).