Madinah is a blessed city

Every pilgrim must visit the abode of the most revered Prophet (SAW). Usually a pilgrim stays in the most sacred and beautiful land on earth for eight days. Abu Huraira (RA) quotes the beloved Prophet (SAW) as having said, “I was ordered to migrate to a town which will swallow (conquer) other towns and is called Yathrib and that is al Madinah, and it turns out (bad) persons as a furnace removes the impurities of iron.” (Al Bukhari).
The stay in Madinah provides the Haji an opportunity to get perfect. Jabir (RA) narrates: A Bedouin came to the Holy Prophet (SAW) and gave the Bai’a (pledge) for embracing Islam. Next day he came with  a fever and said (to the Prophet SAW), “Please cancel my pledge (of emigrating to Madinah).” The Holy Prophet (SAW) refused that request three times and said, “Al Madinah is like a furnace, it expels out its Khabath (impurities, evil and bad persons etc) and selects the good ones and makes them perfect.” (Al Bukhari).
Therefore, a pilgrim has to exercise utmost care and caution during his stay in the sacred city. He must bear in mind that he has not come to a picnic spot. A wrong deed will take him out of the abode of the Holy Prophet (SAW).
Madinah is a Haram (sanctuary) between two mountains. Therefore, its trees should not be cut, no heresy should be innovated and nor any sin committed in it, and whosoever innovates in it a heresy or commits a sin then he will incur the curse of Allah, the angels and all the people. (Al Bukhari narrated by Abu Huraira RA).
Another hadith narrated by Hazrat Ali (RA) adds the following sentences, “(N)one of his compulsory or optional good deeds of worship will be accepted.”
In Madinah the pilgrim has to take care while dealing with the people of the sacred city. “None plots against the people of al Madinah but that he will be dissolved (destroyed) like the salt is dissolved in water,” narrated by Sa’d (RA) and reported by Imam Bukhari (RA).
A big fat book is needed to describe the virtues of the holy city. However, for the information of the pilgrims Madinah is the abode of peace, love and harmony. Even Dajjal cannot enter the holy city. Hazrat Abu Bakr (RA) narrated: The Holy Prophet (SAW) said, “The terror caused by al Masih, ad Dajjal will not enter al Madinah and at that time al Madinah will have seven gates and there will be two angels at each gate (guarding al Madinah).” (Al Bukhari).
A pilgrim has nothing to worry about during his stay in al Madinah as according to Abu Huraira (RA), “There are angels guarding the entrances (or roads) of al Madinah. Neither plague nor ad Dajjal can enter it.” (Al Bukhari).