You can spend the whole day at Montserrat so you can take your time exploring the Montserrat Monastery. Alternatively if you don't have much time on your holiday you could take a half day visit to Montserrat. You can take a train from Barcelona to go to Montserrat.

To truly experience the spiritual and natural beauty of Montserrat, you should plan to spend at least 5 to 7 hours on the mountain, which essentially makes it a full-day trip from Barcelona. A 5-hour visit allows enough time to take the Aeri (cable car) or Rack Railway up the mountain, visit the Basilica of Montserrat, and see the famous "Black Madonna" (La Moreneta). If you time it correctly (typically at 1:00 PM on weekdays), you can also hear the world-renowned Escolania Boys' Choir perform. For those who enjoy the outdoors, a 7-hour stay allows you to take the Sant Joan funicular even higher to the summit, where you can hike various trails offering panoramic views of the Catalonia region. Budgeting extra time is essential for browsing the local market where monks sell honey and cheeses, and for a leisurely lunch at the buffet or restaurant. If you only have 2 or 3 hours, you will likely feel rushed and miss out on the incredible hiking paths that make Montserrat more than just a religious pilgrimage site.