Sources - Midrash

The Rabbis taught in a Baraisa: Whoever did not see Jerusalem in its splendor never saw a delightful city in his life. Whoever did not see the Temple when it stood never saw a magnificent structure in his life.

b. Sukkah 51b

The Land of Israel sits at the center of the world; Jerusalem is in the center of the Land of Israel; the Temple is in the center of Jerusalem; the Sanctuary is in the center of the Temple; the ark is in the center of the Sanctuary; and the foundation stone, out of which the world was founded, is in front of the Sanctuary.

Tanhuma Buber, Leviticus, Kedoshim

And so we find in the days of Herod, when they were engaged in building the holy Temple, the rains would fall only at night when no work was being done. The next day, the wind would blow, the clouds would disperse, and the sun would come out. And the people would go out to their work knowing that the work of Heaven was in their hands, i.e., their work was approved by Heaven.

b. Ta’anit 23a

It was said: Whoever did not see the Temple building erected by Herod has not seen a truly beautiful building in his lifetime.

b. Bava Basra 4a

Ten miracles were performed for our fathers in the Temple:
No women ever miscarried from the odor of the sacrificial flesh;
The sacrificial flesh never became putrid;
No fly was ever seen in the slaughterhouse;
No pollution ever befell the High Priest on Yom Kippur;
The rains never extinguished the fire of the woodpile on the alter;
The wind never prevailed over the column of smoke;
There was never found a disqualifying defect in the Omer or in the Two Loaves, or in the Shewbread;
The people stood tightly pressed together, yet prostrated themselves with ease;
Neither snake nor scorpion ever injured anyone in Jerusalem;
And no man ever said to his fellow: the space is too narrow for me to lodge overnight in Jerusalem.

m. Avot 5:5

Rabba expounded: What is the meaning of that which is written: “How lovely are your footsteps in sandals, O daughter of the noble.” (Song of Songs 7:2) [It means:] How lovely are the footsteps of Israel when they ascend to Jerusalem to celebrate the festival.

b. Hagigah 3a