From the Wikipedia page on Bulls Cross 
Since 1972 the headquarters of Lee Valley Regional Park Authority (LVRPA). The house was built in 1818 by George Ferry & John Wallen for H. C. Bowles. The plantsman E.A. Bowles created the famous Myddelton House Gardens in c.1900 which are open to the public. The grounds contain the original Market Cross of Enfield Town, which is subject to a Grade II preservation order. There is also a modern museum with artefacts and displays relating to the life and work of E.A. Bowles.
The Historic England page is