I have visited the National Holocaust Centre on several occasions. These have included a field trip with my students, a study visit for my own benefit, and a couple of visits to hear Holocaust survivors give their testimonies.
The Centre is a bit off the beaten track, but has beautiful grounds studded with thought provoking statuary and themed memorials. The internal spaces include a lecture theatre, library, and the museum.
The Camps Pillar is a potent symbol, as it represents the millions who died in the six camps named upon it, and soil from each lies beneath it. Other memorials include one dedicated to the Swedish diplomat, Raoul Wallenberg who rescued thousands to only perish himself.

Raoul Wallenberg Monument
This being an educational centre, there are several features which focus on children. These include a memorial where you are challenged to place a stone to remember the lost children, a monument to the hidden children and those that protected them, and a bronze sculpture representing the children of the Kindertransport.
The Centre also has regular educational events, and Holocaust survivors regularly tell their stories at the venue. I have heard Kitty Hart Moxon and others here, and their accounts are powerful and moving.
The museum shows the progression of the isolation and persecution of the Jewish community, and the subsequent events of the Holocaust. It is deeply touching, and calls for some soul searching on how one might respond in such circumstances.
While not the main focus of such a visit, their are some nice gardens, notably the roses of the memorial garden. There is also a book shop and places to have lunch.
This is a place to take your time to take it in. It is place to learn, to reflect, and to reflect again. It is well worth the visit.
Padre