Think about the city you are living in now. Are there designated places to go to worship? Think about your neighborhood. Does it have walls around it, a gate to let in pre-approved people? Some cities and some neighborhoods are like this.
And then there's the new city described in the book of Revelation.
No temple. We won't need some special, set-aside place to go to worship God. God will be present to us wherever we are.
No shut gates. We won't need a barrier to keep out folks not like us. People from all nations will come in, and bring with them gifts to benefit our lives.
Further, we won't even need street lights, because the glory of God the Almighty will provide all the light we need through the Lamb as our lamp. (Also see Isaiah 60:19-20; Zechariah 14:7.) My own imagination limits my ability to understand this one other than metaphorically.)
Instead of a special place to worship God, the whole city is infused, illuminated, and open.
Yet, not completely accessible. (Also see Isaiah 35:8-9).