The Midsummer Fire Festival of WoW Classic is an event that celebrates the hottest times of year, taking place then as well. The event starts on the real world Summer Solstice and generally lasts for about a week. During this time, players can celebrate the heat by completing quests to collect Burning Blossom, which they can then toss into a bonfire to gain a buff of 3% Critical Strike to both melee and spell damage. There are also a number of other rewards, including a massive amount of experience and gold for completing all of the quests and a unique vanity head slot item.

Differences in the Midsummer Fire Festival Between Classic and Retail

While the concept of the Midsummer Fire Festival has not changed much -- lighting bonfires across Azeroth to celebrate the summer solstice -- there are a number of differences between the old Classic and Retail versions of the holiday.
There are fewer bonfires in Classic -- 26 in all, 16 divided evenly between each continent, 6 located in the major faction cities, and 4 inside dungeons, with specific quests to visit them. In Retail, there are bonfires located in nearly every zone across multiple continents.
In Classic, Burning Blossom is the fuel you need to ignite or steal the flame from a Midsummer bonfire and you receive rewards primarily in the form of experience and buffs. In Retail, Burning Blossom also acts as a currency to purchase clothing, pets, and toys from special Midsummer vendors.
In Classic, the Engineer's Explosive Extravaganza fireworks show occurs on the last night of the Midsummer Fire Festival, coinciding with the United States' July 4th Independence Day. In Retail, the fireworks are simply incorporated as part of the Midsummer Fire Festival itself.
In Classic, there are no dailies associated with the Fire Festival.
In Classic, you are directed to steal the opposite faction's flame. In Retail, the goal is to extinguish the flame. Small semantic difference.

Quests of WoW Classic Midsummer Fire Festival

The main activities during the Midsummer Festival are the quests – the great majority of which are meant for max level characters, as they guide players not only to high level zones, but into opposing enemy faction territory. If you are not at or near max level, it is not at all recommended that you attempt any more than the initial starting quest. With the exception of the quests that lead you to your opposing faction’s cities to steal their flame, the quests are almost identical for either Horde or Alliance players

The Festival of Fire: This is the very beginning quest for the Midsummer Festival and is the only quest that can be completed by any players under the level of 50. To start the quest, and all of the other quests for this event, simply find the Festival Talespinner in your capital. For this quest they will instruct you to go to each of your faction’s capital cities and touch the sacred bonfire there.

A Light In Dark Places: One of the many quests you can only do during this festival, “A Light in Dark Places” isn’t just a reference to The Lord of the Rings. It’s the flip side of the starting quest, except this time you go to dangerous and obscure places to complete your mission, so only high-level players are eligible. These are some of the highest level dungeons and raids in the game, lead Alliance and Horde players into the darkest and most dangerous known places in Azeroth to seek the flame in them. These are the four major dungeons of Azeroth.

The Thieving Quests: This is where the factions differ from one another a bit more, as these quests guide players to their opposing faction’s capitals to steal their sacred flame from their bonfires. Only PvPers or higher level characters will be able to tackle this quest. That’s even more dangerous than the ones that require visits to max-level dungeons. If you can’t stealth or raid your way in, you have to skip the quests or find another way.

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