Lets see some of the similarities between archaea and bacteria here on this page:
Similarities between Archaea and Bacteria
1. Archaea have generally the same shape, size, and appearance as bacteria.
2. Like bacteria, Archaea multiply by binary fission and move primarily by means of flagella.
3. These morphological similarities can make it difficult to visually tell a bacterium and anarchaean apart.
4. Additionally, archaea are more phylo-genetically similar to eukarya than bacteriais to either of them.