What is there to say about the Taj Mahal? The iconic tomb, created out of love for a wife, lives large in a traveler's imagination; it may be the main reason you've booked an Indian river cruise in the first place. A stop in Agra is the centerpiece of all Golden Triangle tours and so you'll want to make the most of the stop.
The Taj Mahal is a creation of the Islamic Mogul dynasty and Agra remains a Muslim city, even today. From your hotel, you'll hear the call to prayer, and the women on the street are often fully covered. The Taj Mahal has no dress code, but you'll have to take your shoes off to go inside. Some guides provide shoe booties that serve the same purpose.
Note: It's a three-hour drive between Delhi and Agra, so settle in (the buses do take breaks at surprisingly modern highway rest stops). Keep your eyes out the window, however; the scenery changes from urban to rural once you leave city limits and the green fields can appear restful after the chaos of the city.
Tap water, even in major hotels, is undrinkable. Since 80 percent of the diseases in India are spread through bad water, avoid tap water and only accept bottled water from your hotel or from a known tour provider. Brush your teeth with bottled water and avoid ice. You'll also want to stay away from unpeeled fruit and anything that is uncooked.
Wear mosquito repellant with a high concentration of DEET and cover up. You'll also want to wear socks or get booties for your shoes, as they're not allowed inside the Taj Mahal.
Currency in Agra is the Indian rupee. Bring cash, in crisp dollar bills, and exchange at the airport when you arrive. Check www.xe.com for current exchange rates. ATMs, while prevalent, do not always have money and withdrawal amounts are often controlled by the government. Luxury hotels will often exchange small amounts. Credit and debit cards are accepted by major hotels and shops, but cash is preferred for small vendors and markets.
Hindi -- the country has more than 1,500 dialects -- and English are the official languages. Almost everyone in the tourist trade speaks the latter.