Korea is back on coinmarketcap
Here you can see a huge spike in the volume, up to 800 million USD in seconds up from 224 million, so this w

You can see that it never got this high in volume ever

Looking into the markets we can see

| # | Source | Pair | Volume (24h) | Price | Volume (%) | Updated |
|---|---|---|---|---|---|---|
| 1 | Upbit | ADA/KRW | $785,700,000 | * $1.08 | 73.00% | Recently |
Looking on upbit it shows they are in operation for a while
So we can assume that coin market cap just added them back in and skewed the graph.
Now looking at the data about the exchange itself here https://coinmarketcap.com/exchanges/upbit/

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