Shows and Events - Diamond Service Grading
Diamond Service Grading presents

Sonoma County
Card & Collectibles Show

August 15–16, 2026 · DoubleTree by Hilton · Rohnert Park, CA

Diamond Service Grading is bringing the hobby to Sonoma County. Join collectors, dealers, and grading enthusiasts from across Northern California for a two-day card show — plus an exclusive VIP Kick-Off the night before.

Get weekend tickets Become a vendor Meet the signers Book a room Event details
Two-day show VIP Kick-Off Aug 14 On-site grading Discounted hotel rooms Ample free parking
Diamond Service Grading
DSG August 15th and 16th Card Show vendor flyer

Two days of cards

August 15–16, 10 AM–5 PM at the DoubleTree by Hilton in Rohnert Park.

VIP Kick-Off Night

August 14, 6–10 PM — get in before the doors open to the public.

Need a room?

A limited block of discounted rooms is open at the host hotel. Book today.

Buy◆Sell◆Trade◆Grade

Meet & greet · Autograph signing

Meet living baseball history

The Rohnert Park Card Show isn’t just tables and toploaders — it’s a chance to shake hands with the men who lived the game. Three featured signers will be on-site at the DoubleTree for a meet, greet, and autograph session, including Negro Leagues veterans Dennis “Bose” Biddle and W. James Cobbin. Bring a ball, a card, or a piece of memorabilia — and take home a signature that tells a story. Tap any card below for the full profile.

Negro League Legend Dennis ‘Bose’ Biddle, former Chicago American Giants pitcher and Negro Leagues legend
Chicago American Giants · Pitcher

Dennis “Bose” Biddle

Beat the man who once beat Satchel Paige

He took the mound for the Chicago American Giants in 1953 at just 17 — among the youngest ever to play in the Negro Leagues. Today he’s founder and president of Yesterday’s Negro League Baseball Players Association, fighting for the legends who built the game.

Read his story
Negro League Legend W. James ‘Jim’ Cobbin, former Indianapolis Clowns outfielder and Negro Leagues legend
Indianapolis Clowns · Outfielder

W. James “Jim” Cobbin

Roamed the outfield as “the Ohio Highway Patrol”

A .317 career hitter with blistering speed, Cobbin signed with the Indianapolis Clowns in 1956. Offered a deal inside a segregated big-league system, he chose the dignity of the Negro Leagues — and later built a charity and museum to keep their story alive.

Read his story
Negro League Legend
New York Black Yankees · Pitcher

Don “The Rook” Porter

Boarded the barnstorming bus at just sixteen

He broke into pro ball with the New York Black Yankees in 1957 while still a high-school sophomore, then moved up to the famed Indianapolis Clowns — Hank Aaron’s old club — the next year. A pitcher and outfielder through the twilight of the Negro Leagues, he was inducted into Yesterday’s Negro League Hall of Fame in 2017.

Read his story
Bring something to sign. A vintage baseball, a custom card, or a piece of Negro League memorabilia — the signers will autograph whatever you bring. If it’s a trading card, hand it straight to Diamond Service Grading afterward to be graded and encapsulated right there at the show. Card grading and encapsulation only.
Get show tickets
Passes & admission

Get your tickets

Pick your day, or go all-in with the VIP weekend pass. Tickets are handled securely through Diamond Service Grading's event checkout.

DSG August 14th Friday Card Show VIP poster
VIP · All-access
Friday VIP + Weekend Pass
Fri, Aug 14 · VIP Night + full weekend
$100 /pass
  • VIP Kick-Off Night, Aug 14 (6–10 PM)
  • Weekend admission — both show days
  • Early-access entry ahead of the crowd
Get VIP pass
DSG August 15th Saturday Card Show Day 1 poster
Saturday — Day 1
Sat, Aug 15 · 10 AM–5 PM
$10 /day
  • Full-day general admission
  • Thousands of cards from top vendors
  • Drop cards for on-site grading
Get Saturday ticket
DSG August 16th Sunday Card Show Day 2 poster
Sunday — Day 2
Sun, Aug 16 · 10 AM–5 PM
$10 /day
  • Full-day general admission
  • Fresh deals and restocked tables
  • Drop cards for on-site grading
Get Sunday ticket
Three trading cards encapsulated in Diamond Service Grading slabs
Dealers & vendors

Reserve your booth

Sell to collectors from across Northern California over both days of the show. Every table covers the full weekend — set up Saturday and Sunday, August 15–16.

6ft Table
Both days · Aug 15–16
$200 /weekend
Sold out
8ft Table
Both days · Aug 15–16
$250 /weekend
Booths are limited and assigned in the order they're purchased — reserve early to lock in your spot. Vendors can stay on-site too: use the show room block below.
Reserve a booth Book a room
Two days, one weekend

Thousands and thousands of cards from the top vendors

Whether you're buying, selling, trading, or getting cards graded on the spot — this is the weekend for it.

Buy, sell & trade

Hundreds of dealer tables stocked with vintage, modern, sports, TCG, and non-sports cards.

Grade on-site

Bring cards to drop off for grading with Diamond Service Grading, right there at the show.

Meet the hobby

Collectors, dealers, and breakers from across the Bay Area, the North Bay, and beyond.

Know before you go

Event details

The Rohnert Park Card Show is shaping up to be one of the best hobby events in Northern California this year. Mark your calendar, grab your tickets, and bring a bag — you're going to need it.

At a glance
Everything you need for the weekend.
  • VIP Night
    August 14 · 6–10 PM
  • Card Show
    August 15–16 · 10 AM–5 PM
  • Location
    DoubleTree by Hilton, Rohnert Park, CA
  • Admission
    $10 single day · $100 VIP weekend
  • Vendor Tables
    6ft $200 · 8ft $250 (full weekend)
  • Hotel Room Block
    Discounted rooms at the venue · Group code CDT91F
Venue
DoubleTree by Hilton Hotel Sonoma Wine Country
DoubleTree by Hilton Hotel Sonoma Wine Country
One DoubleTree Drive
Rohnert Park, CA 94928

Conveniently located off US-101 with ample parking and full hotel amenities. Whether you're coming in from the Bay Area, the North Bay, or out of town — it's an easy venue to get to and a comfortable place to spend the weekend.

Get directions Need a room? See the room block
Where to stay · Hotel room block

Need a room? Stay where the show is.

A limited number of discounted rooms have been blocked off at the DoubleTree by Hilton Sonoma Wine Country — the same hotel hosting the show. Roll out of bed and onto the show floor. Rooms are released first come, first served, so book today.

Group booking code
CDT91F
Use this code when you call the hotel or book on Hilton.com. The direct link below applies it for you.
Fastest
Book online

One link, one tab, done. Our group rate is already applied — pick your dates and confirm. No code to type in.

Book your room
Reserve by phone

Call the hotel reservations line, select option 1, and give the booking code CDT91F

(707) 584-5466
Call the hotel
Book on Hilton.com

Prefer to book through your own Hilton Honors account? Search the DoubleTree Sonoma Wine Country, open Special Rates, and enter Group Code CDT91F

Open Hilton.com
Rooms are limited. The block is a fixed number of rooms at a discounted group rate, released first come, first served. Rates and availability are set by the hotel and can change at any time, and rooms outside the block are booked at standard rates. Reservations, changes, and cancellations are handled directly by the DoubleTree. Questions about the show itself? Email support@dsggrading.com

See you at the show

The Rohnert Park Card Show is going to be one of the best hobby events in Northern California this year — grab your tickets, reserve a table, book a room, and bring a bag.

Get weekend tickets Reserve a booth Book your room

Questions about the show? Email support@dsggrading.com