If Philadelphia was ever its own, semi-isolated island — like some sort of urban Brigadoon — it's not now.

The classical music traffic in and out of town is heavier and healthier than ever, allowing local audiences to hear new voices and new ideas from a greater geographical spread, and also allowing cultural institutions to broaden their fund-raising bases.

Maybe those kinds of benefits didn't pan out when the Philadelphia Orchestra visited bankrupt Mongolia this year. But the classical music world is one with a long-term arc. Some of the best things in 2017 were years in the making. Some highlights:

Rossini's Tancredi. Initially, Opera Philadelphia's February production was anything but promising, even with the great Stephanie Blythe cast in the title role. Serious Rossini can be dead on arrival, but not this opera, which shows the young composer discovering what he could do, writing one of the most introspective endings of his entire career, and generally creating roles that great singers can live in. Blythe was an essential component here, but so were Brenda Rae and conductor Corrado Rovaris.

Opera at the edge. The great thing about the operatic cluster created by Opera Philadelphia's O17 Festival was quality control. Nothing felt haphazard, ill-considered, or insubstantial. The point is not how much of it you liked but that there was so much to bounce off of your brain cells. Even if a piece didn't speak to you, it was still to be respected.

Not to be overlooked, though, is Sophia's Forest, presented around the same time with electronic instruments custom-built by the Drexel University ExCITe Center. I missed it but caught up with a video that verified much of the rapturous reaction I'd heard from others. A searingly introspective study on immigrant children, the opera was full of vocal lines reflecting psychological depths but also electronic music effects that added greatly to the dreamlike atmosphere. The superb soprano Kiera Duffy was a major plus in the leading role.

The Broadway/opera hybrids. Great things can be said with a light touch. The hit musical Dear Evan Hansen is celebrating a year on Broadway, but what's unexpected is the kind of recognition that has come to the soft-rock but dramatically alert score by Justin Paul and Ardmore's Benj Pasek. The high-tone Gramophone magazine reviewed the original cast album. The Juilliard School bookstore displays the score in the front window.

Peter Serkin on tour with the Curtis Symphony Orchestra. For decades, this charismatic pianist has been a somewhat aloof presence, but perhaps mainly in the minds of those who are afraid to talk to him. Night after night during his May European tour with the Curtis Symphony Orchestra, the 70-year-old pianist played Brahms with go-for-broke intensity.

When I'd bump into him in some concert-hall canteen, we'd suddenly be chatting about everything from household pets to the importance of rubato in Schoenberg. I'd meant to ask if he would please revisit his early signature piece, Bach's Goldberg Variations. Later, I found out I didn't have to: He was back with Bach in a visit to Japan. And because everything there is recorded, it's only a matter of time before that performance reaches our ears.

The Philadelphia Orchestra's (sort of) visit to Mongolia. Weeks before the spring tour departure, word arrived that the long-planned June Mongolian debut was being scuttled by the country's long-brewing economic crisis. So the State Department footed the bill for a smaller version of the orchestra to visit the capital city of Ulaanbaatar. The players did their best to make an impression in that sprawling city of unfinished skyscrapers and yurts, though grabbing the attention of the populace isn't easy.

In fact, the locals were having a perfectly enjoyable summer — crisis? what crisis? — bopping off for a Gobi Desert holiday in their SUVs, often departing from designated roads, just driving over the terrain, picking up Mom at an address-free yurt where she had retired to a less-stressful life, perhaps on advice from the local shaman.

Discovery of the year: Canadian composer Claude Vivier (1948-83) has long been known as one of the great might-have-beens. During the Curtis tour, I stumbled upon a recording of his opera Kopernikus by Opera Factory Freiburg, which creates its own unique operatic world with a free-associative narrative, half sung and half spoken with all sorts of extended vocal techniques, employed with a confidence suggesting this piece was always meant to be.

Wisecrack of the year. In January, mezzo-soprano Susan Graham was introducing the folksy Songs of the Auvergne to a Philadelphia Orchestra audience, pointing out how so much of the music is about animals, birds, etc. Then she departed from the script with mock-ingenuousness: "But, you know, I hear they've discovered a new kind of cuckoo bird — that tweets!" Reportedly, the audience missed a beat, got the joke, and — as Philadelphia is a mainly Democratic town — laughed …well, mostly.

The Yuja report. The concert world can't help but be fascinated with how little fabric Yuja Wang gets away with wearing at her concerts. The Curtis Institute graduate has forged new paths in ever-higher heels and ever-tinier dresses. Washington Post critic Anne Midgette, reporting on Wang's Nov. 30 concert at the Kennedy Center, wrote that the pianist "appeared to have forgotten her dress altogether and looked as if she were playing in her underwear." Whether or not she's trying to out-Cher Cher, she remains one of the finest pianists out there.

New year's wish. The pianist I would most like to hear in person in 2018 is the young Italian talent Beatrice Rana. Beyond having a complete command of the keyboard, she has an originality of insight that has made her a major personality, even though she's only in her mid-20s. Her 2017 recording of the Goldberg Variations on Erato is a marvel. And various radio broadcasts around the world show that there's much, much more to come.