This image shows a magnified view of two villi.  Note that each villus consists of a projection of the lamina propria covered by a  layer of simple columnar epithelial cells, mucus-containing goblet cells and a scattering of enteroendocrine cells.  Tiny projections of the plasma membrane of the epithelial cells of the mucosa called microvilli (difficult to see with a light microscope) further increase the absorptive surface area of each villus.  It is across the epithelium-coated villi that nutrients, water and electrolytes are absorbed.