More than 67,000 football fans are expected to attend the all-English Champions League final between Liverpool and Tottenham Hotspur at the Wanda Metropolitano stadium in Madrid on Saturday.
Liverpool are veterans of the competition, having won this title five times previously. They were also beaten in the final last year by Real Madrid.
It's Spurs' first appearance in a Champions League final.
Dozens of chartered flights arrived on Friday and authorities expect many of those arriving in the Spanish capital are without tickets or lodging.
Spanish police are using drone surveillance and an anti-drone attack operation.
Liverpool fans flooded Madrid's Central Square as they drank and chanted songs to support their team.
Liverpool defender Andy Robertson said there was a good atmosphere in the Liverpool camp: "It's relaxed, it's pretty similar to last year. We were relaxed last year. Obviously, we will have the same nerves going on in the game, but positive nerves of a big game and Tottenham will be the same.
"We've had a good rest and now we are good to go. We are trying to get that into our legs now and, you know, we just want the game to start now. "
But Spurs are equally determined. Midfielder Dele Alli said: "I think we have proved that we are up there with the best teams in the world and you know it is another opportunity to show that and to win the Champions League for Tottenham and to get the reward for all the hard work we have been putting in on the training field.
"I think the fans deserve it as well; they have supported us over these years together. I think we have shown improvements each year, whether it be in the Premier League or the Champions League.
We are heading in the right direction. We are obviously happy to be in the final but we are going there to win."