For centuries this hill has been a place of spirituality: the Druids, the Gauls, the Romans all came here to worship. Then in 1875 the Roman Catholic church began to build a basilica, which was finished in 1914 and consecrated in 1919. Made of a travertine stone, which remains white despite weathering and pollution, the church has one of the largest mosaics in the world in the apse and a dome you can climb to get even greater views of Paris stretching away to the south of Montmartre.
Sacre Coeur is open every day from 6am until 10:30pm, and mass is held regularly in the church from Monday to Thursday at 11:15am, 6:30pm and 10pm, on Friday at 3pm, and on Sunday at 11am, 6pm and 10pm. The dome is open from 9am until 7pm (6pm in winter).
The easiest way to reach Sacre Coeur is by metro to Anvers, across the road and along the narrow cobbled street up the hill. At the top of this short street, to the left, there is a funicular to take you up the steep hill. You can use your metro tickets for the funicular. If you turn right instead, you can climb the hill via around 200 steps.
Once at the top, enjoy the view back over Paris. To see the Eiffel Tower you’ll need to turn left out of the funicular (rather than right towards the church), and walk along the road a few yards — then you’ll see the Eiffel Tower over the rooftops. Handily someone has cut a square hole in the mesh fence for you to take photos.
When you’ve finished exploring inside Sacre Coeur’s many side chapels, head right out of the church and follow the road around the hill. There you’ll find a lovely little village and marketplace full of artists and cafes. Wander down the hill along steep, character-filled streets and at the bottom you’ll find the other metro station in the area: Abbesses (somewhat hidden behind a carousel in the small square Place des Abbesses, on Rue des Abbesses, a good shopping street).