In 2000, LEGO released 22 Castle sets across 2 subthemes, all of these sets have been retired. Subthemes for that year included Knights Kingdom I and Ninja. For that year, the total price of all retail sets cost $322, today those sets are valued around $4,982, a growth of 1449%.
Most valuable 2000 LEGO Castle set
6098 King Leo's Castle $1,175.84
Highest growth 2000 Castle set
3346 Three Minifig Pack Ninja #3 +11924.05%
Largest 2000 LEGO Castle set
6091 King Leo's Castle 529 pieces
Most owned 2000 Castle set
6094 Guarded Treasure
22 sets

1286 King Leo's Spear Cart

Theme / Subtheme Castle / Knights' Kingdom I
Year 2000
Pieces / Minifigs 22 / 1
Availability Retired
1286 LEGO Knights' Kingdom I King Leo's Spear Cart
Retail $1.99
Value $39.24
Growth  +1871.9%
Annual growth 12.2%

1287 Richard's Arrowseat

Theme / Subtheme Castle / Knights' Kingdom I
Year 2000
Pieces / Minifigs 15 / 1
Availability Retired
1287 LEGO Knights' Kingdom I Richard's Arrowseat
promotional
Value $28.98
Annual growth 2.3%

1288 Bull's Fire Attacker

Theme / Subtheme Castle / Knights' Kingdom I
Year 2000
Pieces / Minifigs 24 / 1
Availability Retired
1288 LEGO Knights' Kingdom I Bull's Fire Attacker
promotional
Value $18.33
Annual growth 4.1%

1289 Weezil's Stone Bomber

Theme / Subtheme Castle / Knights' Kingdom I
Year 2000
Pieces / Minifigs 22 / 1
Availability Retired
1289 LEGO Knights' Kingdom I Weezil's Stone Bomber
promotional
Value $80.23
Annual growth 8.8%

3344 One Minifig Pack Ninja #1

Theme / Subtheme Castle / Ninja
Year 2000
Pieces / Minifigs 9 / 1
Availability Retired
3344 LEGO Castle One Minifig Pack Ninja #1
Retail $4.99
Value $254.56
Growth  +5001.4%
Annual growth 9.2%

3345 Three Minifig Pack Ninja #2

Theme / Subtheme Castle / Ninja
Year 2000
Pieces / Minifigs 21 / 3
Availability Retired
3345 LEGO Castle Three Minifig Pack Ninja #2
Retail $4.99
Value $387.22
Growth  +7659.9%
Annual growth 11.1%

3346 Three Minifig Pack Ninja #3

Theme / Subtheme Castle / Ninja
Year 2000
Pieces / Minifigs 22 / 3
Availability Retired
3346 LEGO Castle Three Minifig Pack Ninja #3
Retail $4.99
Value $600.00
Growth  +11924.0%
Annual growth 14.1%

4801 Defence Archer

Theme / Subtheme Castle / Knights' Kingdom I
Year 2000
Pieces / Minifigs 15 / 1
Availability Retired
4801 LEGO Knights' Kingdom I Defence Archer
Retail $1.95
Value $37.12
Growth  +1803.6%
Annual growth 8.5%

4806 Axe Cart

Theme / Subtheme Castle / Knights' Kingdom I
Year 2000
Pieces / Minifigs 28 / 1
Availability Retired
4806 LEGO Knights' Kingdom I Axe Cart
Retail $2.99
Value $41.70
Growth  +1294.6%
Annual growth 8.2%

4807 Fire Attack

Theme / Subtheme Castle / Knights' Kingdom I
Year 2000
Pieces / Minifigs 24 / 1
Availability Retired
4807 LEGO Knights' Kingdom I Fire Attack
Retail $1.95
Value $39.84
Growth  +1943.1%
Annual growth 9.0%

4811 Defense Archer

Theme / Subtheme Castle / Knights' Kingdom I
Year 2000
Pieces / Minifigs 15 / 1
Availability Retired
4811 LEGO Knights' Kingdom I Defense Archer
Retail $1.95
Value $33.05
Growth  +1594.9%
Annual growth 8.3%

4816 Knights' Catapult

Theme / Subtheme Castle / Knights' Kingdom I
Year 2000
Pieces / Minifigs 50 / 2
Availability Retired
4816 LEGO Knights' Kingdom I Knights' Catapult
Retail $4.99
Value $116.67
Growth  +2238.1%
Annual growth 8.8%

4817 Dungeon

Theme / Subtheme Castle / Knights' Kingdom I
Year 2000
Pieces / Minifigs 38 / 2
Availability Retired
4817 LEGO Knights' Kingdom I Dungeon
Retail $4.99
Value $114.47
Growth  +2194.0%
Annual growth 9.2%

4818 Dragon Rider

Theme / Subtheme Castle / Knights' Kingdom I
Year 2000
Pieces / Minifigs 11 / 1
Availability Retired
4818 LEGO Knights' Kingdom I Dragon Rider
Retail $4.99
Value $255.34
Growth  +5017.0%
Annual growth 11.2%

4819 Bulls' Attack Wagon

Theme / Subtheme Castle / Knights' Kingdom I
Year 2000
Pieces / Minifigs 49 / 2
Availability Retired
4819 LEGO Knights' Kingdom I Bulls' Attack Wagon
Retail $4.99
Value $124.16
Growth  +2388.2%
Annual growth 10.1%

6026 King Leo

Theme / Subtheme Castle / Knights' Kingdom I
Year 2000
Pieces / Minifigs 21 / 2
Availability Retired
6026 LEGO Knights' Kingdom I King Leo
Retail $4.99
Value $80.00
Growth  +1503.2%
Annual growth 8.9%

6032 Catapault Crusher

Theme / Subtheme Castle / Knights' Kingdom I
Year 2000
Pieces / Minifigs 56 / 1
Availability Retired
6032 LEGO Knights' Kingdom I Catapault Crusher
Retail $5.99
Value $56.79
Growth  +848.1%
Annual growth 7.0%

6091 King Leo's Castle

Theme / Subtheme Castle / Knights' Kingdom I
Year 2000
Pieces / Minifigs 529 / 8
Availability Retired
6091 LEGO Knights' Kingdom I King Leo's Castle
Retail $89.99
Value $968.39
Growth  +976.1%
Annual growth 7.8%

6094 Guarded Treasure

Theme / Subtheme Castle / Knights' Kingdom I
Year 2000
Pieces / Minifigs 103 / 2
Availability Retired
6094 LEGO Knights' Kingdom I Guarded Treasure
Retail $14.99
Value $86.36
Growth  +476.1%
Annual growth 6.7%

6095 Royal Joust

Theme / Subtheme Castle / Knights' Kingdom I
Year 2000
Pieces / Minifigs 101 / 3
Availability Retired
6095 LEGO Knights' Kingdom I Royal Joust
Retail $19.99
Value $176.24
Growth  +781.6%
Annual growth 7.8%

6096 Bull's Attack

Theme / Subtheme Castle / Knights' Kingdom I
Year 2000
Pieces / Minifigs 313 / 4
Availability Retired
6096 LEGO Knights' Kingdom I Bull's Attack
Retail $49.99
Value $267.54
Growth  +435.2%
Annual growth 6.7%

6098 King Leo's Castle

Theme / Subtheme Castle / Knights' Kingdom I
Year 2000
Pieces / Minifigs 529 / 8
Availability Retired
6098 LEGO Knights' Kingdom I King Leo's Castle
Retail $89.99
Value $1,175.84
Growth  +1206.6%
Annual growth 5.5%