The Beautiful Gate was probably the Nicanor Gate, made of bronze from the city of Corinth. It was on the east side of the temple (see Josephus, War 5.5.3). It had rich decorations of silver and gold plates on its panels. The gold and silver were heavier and more valuable than the plates on other gates.
Solomon’s Colonnade was a covered place to walk on the east side of the temple (see Josephus, War 5.5.1–3; Antiquities 20.9.7).