The Academy of Ancient Music, which celebrates its “golden anniversary” this season, got going just as Handel’s operas began to leave the library at last and reclaim the stage. There they continue to flourish, dazzle and move – which makes any concert performance of them a slightly bittersweet pleasure.

“Tradition is sloppiness,” Mahler the opera conductor is credited with saying. But in the case of old master John Cox’s long-serving Garsington production of the greatest of operatic comedes, not if it’s refreshed with the subtlest insights in to human tensions and frailties.

How much better can a classic get? Sebastian Scotney more or less asked the same question on theartsdesk the last time Giulio Cesare returned in triumph to Glyndebourne. I never saw David McVicar’s justly famous production of what has to be Handel’s most consistently inspired opera live before, but I wonder if every single number can ever have been applauded, as it was last night.

What did they put in the water of Czechia’s central Bohemia/Moravia borderlands? From south to north there's Mahler’s birthplace in Kalište and the city of his youth, Jihlava; the Polička tower where Martinů was born; and finally the Litomyšl brewery which was Smetana’s first home (further east, Janáček and Freud were born six kilometres apart).

It’s somehow typical of the Welsh National Opera I’ve known now for the best part of sixty years that it should confront its current funding difficulties with brilliant productions of two of the more challenging works in the repertory.

Why would anyone want to stage a work like The Merry Widow in this day and age? Silly question. It’s the music, stupid. Of course, it’s an entertaining story and there are some good jokes. But I'd bet that if Heuberger had composed the music to this libretto, as he started doing, instead of Franz Lehár, who took it on afterwards, I wouldn't now be writing about Cal McCrystal’s new Glyndebourne production, or anyone else’s for that matter.

Recreating Handel’s Egypt with a first-rate cast on the summer opera scene could have been the exclusive domain of Glyndebourne, bringing back its revival of David McVicar’s celebrated Giulio Cesare in July. Yet over the Irish sea, in the grounds of a castle with exquisite gardens above the lushly wooded valley of the river Blackwater, they’ve pulled it off. This is a singular triumph of which Caesar would be proud.

Set in a tensely polarised Roman neighbourhood, with an election in the offing and radicals scrapping with reactionaries under poster-plastered walls, Stephen Barlow’s smart update of Tosca from 1800 to 1968 might have felt like a double dose of period-piece on its first outing at Opera Holland Park in 2008. Strongly cast and crisply delivered, this polished and gripping revival gives us Puccini the prophet as well as the pot-boiler. 

Five years after it first clattered onto the Glyndebourne stage, André Barbe and Renaud Doucet’s visually exuberant Die Zauberflöte – featuring everything from dancing carcasses to a monster made out of blue-and-white crockery – continues to dazzle as much as it entertains.

It’s what you dream of in opera but don’t often get: singers feeling free and liberated to give their best after weeks of preparation with a master conductor. Glyndebourne Music Director Robin Ticciati leads the way with a peerless London Philharmonic Orchestra in Bizet’s absolute masterpiece, and Tunisian-Canadian mezzo Rihab Chaieb’s Carmen stuns in a vocally magnificent cast.