The dua when entering a new city is: 'Allahumma Rabbus-samawatis-sab'i wa ma adhlaln, wa Rabbal-aradinas-sab'i wa ma aqlaln, wa Rabbash-shayatini wa ma adlaln, as'aluka khayra hadhihil-qaryah wa khayra ahlaha, wa a'udhu bika min sharriha wa sharri ahlaha wa sharri ma fiha.'
اللَّهُمَّ رَبَّ السَّمَاوَاتِ السَّبْعِ وَمَا أَظْلَلْنَ، وَرَبَّ الْأَرَضِينَ السَّبْعِ وَمَا أَقْلَلْنَ، وَرَبَّ الشَّيَاطِينِ وَمَا أَضْلَلْنَ، أَسْأَلُكَ خَيْرَ هَٰذِهِ الْقَرْيَةِ وَخَيْرَ أَهْلِهَا، وَأَعُوذُ بِكَ مِنْ شَرِّهَا وَشَرِّ أَهْلِهَا وَشَرِّ مَا فِيهَا
Allahumma Rabbus-samawatis-sab'i wa ma adhlaln, wa Rabbal-aradinas-sab'i wa ma aqlaln, wa Rabbash-shayatini wa ma adlaln, as'aluka khayra hadhihil-qaryah wa khayra ahlaha, wa a'udhu bika min sharriha wa sharri ahlaha wa sharri ma fiha.
Meaning: O Allah, Lord of the seven heavens and all they shade, Lord of the seven earths and all they carry, Lord of the devils and all they lead astray, I ask You for the good of this town and the good of its people, and I seek refuge in You from its evil, the evil of its people, and the evil of what is in it.
Source: Musnad Ahmad #18716This dua demonstrates the comprehensive nature of Islamic dua: seeking the good of a place and its people while simultaneously seeking refuge from all forms of harm. Hz. Peygamber would recite this upon seeing any new town, establishing a practice of entrusting every new environment to Allah's care and protection.
اللَّهُمَّ رَبَّ السَّمَاوَاتِ السَّبْعِ وَمَا أَظْلَلْنَ، وَرَبَّ الْأَرَضِينَ السَّبْعِ وَمَا أَقْلَلْنَ، وَرَبَّ الشَّيَاطِينِ وَمَا أَضْلَلْنَ، أَسْأَلُكَ خَيْرَ هَٰذِهِ الْقَرْيَةِ وَخَيْرَ أَهْلِهَا، وَأَعُوذُ بِكَ مِنْ شَرِّهَا وَشَرِّ أَهْلِهَا وَشَرِّ مَا فِيهَا
The Prophet (peace be upon him) never saw a town he wished to enter except that he said upon seeing it: 'Allahumma Rabbus-samawatis-sab'i wa ma adhlaln...'