Sacré-Cœur Basilica is the second highest point of the city and if you climb till the dome (by paying a certain amount) you'll experience a spectacular view including the Eiffel Tower, the Montparnasse Tower, the Panthéon and more.
Right next to the Basilica is the Sinking House of Montmartre
Walk down for 5 mins to see Le mur des Je T'aime, meaning 'I Love You' written 311 times in 250 languages in mural of tiles on a wall in a small garden
Witness an open art gallery called Place du terte.
La Maison Rose is one of the most iconic buildings in Montmartre even before social media hyped it.
Start early by visiting the Eiffel Tower. Metro is the most convenient and cheap way to get around the city.