I arrived at training camp early this morning to loud music coming from the speakers on the practice field. I wanted to take a look to see what was going on, but was told by Oakland Raiders security that I would have to wait for Mike Taylor, the team’s public relations director.

I went upstairs at the Napa Valley Marriott to meet for a minute with Mike, and already the adjoining media room was starting to fill up with writers and TV crews.

It was around 8:15, well in advance of the Raiders’ 16th practice, which was scheduled to start at 8:45.

But this was no normal practice.

The San Francisco 49ers are in town for joint practices against the Raiders. It is the first time in the Raiders’ 13 years of coming to Napa for summer camp that they’ve practiced against another team.

When Mike arrived a few minutes later, we were OK’d to go on to the Redwood Middle School fields.

It was a little overwhelming at first to see from a distance 80 players from the Raiders on one field and 80 players from the 49ers on another field.

But if you love football — and I really, really do — this is the place to be.

The weather was cool with overcast skies as I watched from the sidelines as Niners offensive coordinator Mike Martz ran his quarterbacks — including Kyle Wright, a former Napa resident who played a year of football at Vintage High School — through some passing drills.

I was only a few feet away as Frank Gore led the 49er running backs in a set of drills.

I looked on as the offensive linemen took part in 1-on-1 blocking drills.

It almost took on the look and feel of teams warming up for a game.

Then about 9 this morning, the teams practiced against each other — the 49ers offense against the Raiders defense on one field, the Raiders offense against the Niners defense on the other field.

There were running plays and passing plays, but it was very controlled with no tackling to the ground, even though the teams were in full gear.

Off to the sides of the field, some of the linemen stayed busy, going through 1-on-1 drills.

The Niners, who drove up from Santa Clara Sunday night, wore their red and gold uniforms — the offense in white jerseys (except for the quarterbacks, who wore yellow), the defense in red jerseys.

Afterward, Raiders coach Lane Kiffin and 49ers coach Mike Nolan spoke to reporters. Players were also accessible.

“I think it was very productive,” said Kiffin. “I think it seemed like the defense got the best ends on both sides of the field, which would be normal situation as I just referred to, guys coming in and not knowing what the other side is going to do exactly and what they’ve been doing all offseason.

“We didn’t give any pep talks or anything like that. All we talked about was this is a normal practice, it’s not a scrimmage format, want you to come out like you do every day in practice and come out with the same tempo and it was just interesting to see our guys respond, and get competitive in different environments.

“I can’t speak for them but I thought we pretty much practiced like we usually do. That’s what we push for every day, for guys to compete and run the way they do, regardless of who we’re going against.”

Nolan said: “I thought the tempo was good. We got a lot of work done, and that’s what we came up here to do. It raises that competitive level in guys. It’s important that they look good. There’s a lot of reasons for players to try and perform at their very best.”

Never in my life did I’d think an NFL team would use the locker room at Redwood Middle School, which has close quarters. But all in all, it appears to be working out for the 49ers.

Later, the Niners headed off to a nearby hotel. The teams have an evening practice starting at 7 p.m. tonight.