Hi there!
I had very mixed feelings during and after my visit and would be happy to expand more privately if you message me. Just as a quick overview though--
I would say the general vibe of the school is very grounded in tradition and very Ivy League. So tree-lined walkways on campus, historic buildings, neatly trimmed shrubbery everywhere. You definitely get a college campus vibe from being at Columbia in comparison to schools such as NYU which aren't gated campuses and place you right in the middle of NYC. This could be a pro or con depending on who you are. For me, I wasn't sure I wanted to be so isolated and not so enmeshed with the everyday parts of New York.
The facilities were nice--they have a grad student cafe that only grad students are allowed to access. The Social Work building itself was well-maintained as well. It's not actually on the main campus and you have to walk about two blocks further up to get there. You need to sign in as a visitor if you don't have a CU ID and take the elevator to the 5th floor for the Admissions Office. I was given a brochure for the MSW program and a pamphlet for a self-guided tour of Columbia. The woman I spoke to at the front desk was so kind and sweet and she said there was a possibility I could speak to an Admissions Counselor even though Mondays aren't drop-in hours. I had to explore the building myself--they have an entire library within the building as well as a cafe for students to grab snacks from vending machines and study. The floors with classrooms were nice and each classroom floor had a small kitchenette where you can store food in a fridge and heat food up in the microwave. I also peeked into some classrooms but most were locked. As I headed back to the Admissions Office, I actually ran into an admissions officer giving a small tour to a prospective applicant. I asked to join and they were okay with it. The admissions officer basically showed me the entire building again but also pointed out that Columbia actually hires actors for roleplaying scenarios, and you can record yourself engaging with these actors to practice and reflect on your work afterwards. There's also a quiet room for meditation/prayer/etc... for the students who need it. Afterwards, I was able to speak to the Admissions Counselor, but to be frank, I was a bit put off by him. He was very blase and gave me a bit of attitude.