Security is tight and rules and regulations are very important and must be followed at the Taj Mahal. There are many rules to be followed at the premises of the monument to maintain the holiness of the monument and other rules are mostly for the maintainance and protection of the monument. Remaining rules and regulations are to be followed for the protection of all the tourists visiting the Taj Mahal.

• Arms, ammunition, fire, smoking items, tobacco products, liquor, food, chewing gum, headphones, knives, wire, mobile charger, electric goods (except video camera) such as Tripods, iPods and similar MP3 and music players are prohibited inside the Taj Mahal complex.
• Mobile Phones are allowed but must to be kept switched off.
• Eating and smoking is strictly prohibited inside the Taj Mahal complex.
• Lockers are available at the gates to keep your belongings (of course, at your own risk).
• Avoid carrying big bags and books inside the monument as this may increase your security check time.
• Video camera (handicam) is allowed up to the red sand stone platform at the main entrance gate of the Taj Mahal complex. There is a charge of 25 Rupees per video camera.
• Photography is prohibited inside the main mausoleum, and visitors are requested not to make noise inside the mausoleum.
• Tourists must co-operate in keeping the monument neat and clean by making use of dustbins.
• Avoid touching and scratching the walls and surfaces of the monument as these are old heritage sites that need special care.
• Tourists are advised to hire approved guides and photographers who exhibit their identity cards.
• Tourists are allowed to carry a water bottle inside the monument. Shoe covers, 1/2 litre water bottle and Tourist Guide Map of Agra are provided free of cost with the foreigner's entry ticket for the Taj Mahal.
• Wheelchairs for disabled persons and First Aid Boxes are available at A.S.I. Office inside the Taj Mahal complex. A refundable charge of 1000 Rupees is to be deposited as security before wheelchairs are made available for the disabled.
• All the above mentioned items along with the mobile phones are banned for the night viewing of the Taj Mahal.
• Video cameras are permitted after the security check during night viewing of the Taj Mahal, though extra batteries are prohibited.
• Remember that the Taj Mahal is a religious site and it is best to dress conservatively when visiting the Taj Mahal complex, not only because the Taj Mahal itself is a mausoleum, but also because there are mosques inside the Taj Mahal complex, if you wish to visit them as well.
• There are night viewing sessions on the nights of a full moon and the two days before and after (so five days in total). Exceptions are Fridays (the Muslim sabbath) and the month of Ramadan. Tickets must be purchased 24 hours in advance, starting at 10am, but do not always sell out, so it can be worth looking into it when you arrive even if well after 10am. Tickets only allow viewing from the red sandstone plaza at the south end of the complex, and only for a 1/2 hour window.

Make sure to wear mosquito repellent.

It is a good idea to bring a flashlight, because the interior of the Taj Mahal is quite dark (even during the day) and to fully appreciate the details of the gem inlays, you need a good light.

 

Source: Wikitravel.