The annual festival runs eleven days, from the flag hoisting on 29 August to 8 September, the feast of the Nativity of Mary. It is the largest gathering on this coast — hundreds of thousands of pilgrims, a car procession, and continuous services in several languages.

It is genuinely extraordinary, and it is genuinely difficult. Accommodation triples in price and sells out ninety days ahead, traffic is diverted well outside the town, and darshan queues run for hours. If the atmosphere is the reason you are coming, book early and accept the crowds. If you want to see the Basilica properly, come in December or February instead — you will be able to walk into an empty church at seven in the morning.

Yes, and you will be in the majority. Velankanni has always drawn a substantially non-Christian congregation — Hindus form a large share of the pilgrims, many arriving with the same vows and offerings they would bring to a temple. The Nagore Dargah works the same way. Its tallest minaret, the Periya Manara at roughly 131 feet, was built by Pratap Singh, the Maratha ruler of Thanjavur, in gratitude for a cure — a Hindu king’s gift to a Sufi shrine, still standing after two and a half centuries.

Nobody will ask your religion at either place. This coast has never worked that way, and that shared devotion is a large part of why the route is worth taking.

November to February, with December and January the peak. Greater flamingos arrive with the northeast monsoon when the Great Salt Swamp fills, and numbers can run into the thousands across the lagoons.

Outside those months they are largely absent. From roughly March to September you will see blackbuck, spotted deer, wild boar and the sanctuary’s dry evergreen forest — worth the visit, but not the photograph you may have in mind. We will tell you which applies to your dates rather than let you find out on the day. If flamingos are the reason you want this trip, travel in December or January and we will build in a second game drive.

Modest dress covering shoulders and knees works everywhere on this route. Beyond that, each site differs slightly.

At the Basilica, footwear is removed at the entrance and there is a supervised counter; shorts and sleeveless tops are discouraged. At the Nagore Dargah, heads are covered by everyone including men — scarves are available at the entrance and we carry spares in the vehicle. At the Masilamani Nathar temple in Tharangambadi, standard Hindu temple etiquette applies: footwear off, no leather belts or bags inside.

Photography is restricted inside the Basilica sanctum and the Dargah’s inner chamber. Carry a light scarf and slip-on shoes and you will be comfortable at all three.

Because a day trip gets you the Basilica and nothing else, and the Basilica is not the only thing here.

Within an hour’s drive there is a sixteenth-century Sufi dargah, a Danish colonial town that flew the Dannebrog for 225 years, the site where Bartholomäus Ziegenbalg printed the first Tamil Bible in 1715, a drowned Chola port from the Silappathikaram, and a Ramsar-listed wetland. Almost no operator connects them, which is why the coast is quiet even when Velankanni is not.

Five days also means seeing the Basilica twice — lit at night, and again in the early morning when it is empty. Those are two different buildings, and pilgrims who have only ever come for the day tell us the second is the one they remember.