The City Engineer tells me there were originally 21 parcels deeded to the Hackensack Improvement Commission (Former name for City) between 1911 and 1912. The properties belonged to several people. It probably became Riverside Park shortly after 1912. Here's the list of the 21 "Grantors":
Affidavit of Title Attachment
1. Deed between Jane Parke and the Hackensack Improvement Commission dated May 9, 1912 was recorded in the Bergen County Book 813 of Deeds at pages 486 etc.
2. Deed between Nellie and John Anderson and the Hackensack Improvement Commission dated May 3, 1915 was recorded in the Bergen County Book 916 of Deeds at pages 70 &c.
3. Deed between the Conklin family and the Hackensack Improvement Commission dated August 30, 1926 was recorded in the Bergen County Book 1438 of Deeds at pages 142 &c.
4. Deed between Rachel and John Bogert and Irene and George Wakelee and the Hackensack Improvement Commission, dated January 27, 1911 was recorded in the Bergen County Book 789 of Deeds at pages 598 etc.
5. Deed between Agostino and Adelina Benda and the Hackensack Improvement Commission dated September 15, 1926 was recorded in the Bergen County Book 1439 of Deeds at pages 335 &c.
6. Deed between Louis, Charles, and Irving Conklin and the Hackensack Improvement Commission dated May 24, 1912 was recorded in the Bergen County Book 822 of Deeds at pages 360 etc.
7. Deed between Phoebe Combes and Antoinette and Frederick Stadtlander and the Hackensack Improvement Commission dated November 12, 1909 was recorded in the Bergen County Book 750 of Deeds at pages 153 on.
8. Deed between William and Anna Deubel and Thomas and Anna Lavach and the Hackensack Improvement Commission dated September 20, 1926 was recorded in the Bergen County Book 1443 of Deeds at pages 138 &c.
9. Deed between Louis, Bella, Charles, Edna, frving, and Hettie Conklin and the Hackensack Improvement Commission dated July 24, 1912 was recorded in the Bergen County Book 822 of Deeds at pages 362 &c.
10. Deed between Florence and William Mackey, Trustee of the Hackensack Rod and Gun Club, and the Hackensack Improvement Commission dated December 17, 1910 was recorded in the Bergen County Book 789 of Deeds at pages 601 etc.
11. Deed between the Hackensack Rod and Gun Club and the Hackensack Improvement Commission dated April 6, 1911 was recorded in the Bergen County Book 789 of Deeds at pages 603 etc.
12. Deed between Sarah and Elizabeth Hughes and Mary Hinds and the Hackensack Improvement Commission dated December 27, 1910 was recorded .in the Bergen County Book 774 of Deeds at pages 80 etc.
13. Deed between Marcell and Annie Halstead and the Hackensack Improvement Commission dated November 24, 1911 was recorded in the Bergen County Book 799 of Deeds at pages 656 on,
14. Deed between Sarah and Elizabeth Hughes and Mary Hinds and the Hackensack: Improvement Commission dated December 27, 1910 was recorded in the Bergen County Book 774 of Deeds at pages 82 etc.
15. Deed between Sarah and Elizabeth Hughes and Mary Hinds and the Hackensaek Improvement Commission dated March 14, 1.911 was recorded in the Bergen County Book 778 of Deeds at pages 548 on.
16. Deed between Michael and Anna Leder and William Hughes dated November 20, 1897 was recorded in the Bergen County Book 480 of Deeds at pages 435 etc.
17. Deed between William and Georgianna Taylor and William Hughes dated April 12, 1898 was recorded in the Bergen County Book 466 of Deeds at pages 193 etc.
18. Deed between Jacob Kipp and Michael Leder dated October 25, 1897 was recorded in the Bergen County Book 480 of Deeds at pages 433 etc.
19. Deed between Thomas Achenbach, administrator c.t.a, of Henry Berry deceased, and William Hughes dated July 9, 1897 was recorded in the Bergen County Book 480 of Deeds at pages 439 etc.
20. Deed between Henry Norton; trustee of the property of New York, Susquehanna, and Western Railroad Company; and the City of Hackensack dated October 28, 1946 was recorded in the Bergen County Book 2698 of Deeds at Pages 660 etc.
21. Deed between Oritana Field Club and the Hackensack Improvement Commission dated October 9, 1911 was recorded in the Bergen County Book 795 of Deeds at pages 633 etc.
Today, the park is about 28 acres.