This is a portal triad in the liver.
See if you can pick out the artery (thick red wall, top left), vein (larger lumen, thinner pink wall, bottom), and the bile duct (tall cuboidal epithelium, top right.)
The elements of the portal triad travel inside the liver's portal tracts and branch as they do. The word "portal" means "doorway", as in Harry Potter books. So artery, vein, and bile duct travel through the great doorway and its branches.
The hepatocytes surrounding the portal tract are called "periportal". The rim of hepatocytes immediately around the portal tract's connective tissue are sometimes called the "limiting plate". It should be smooth, and if it is not, one must figure out why.
The portal tracts themselves can be affected by a variety of pathological processes.